Python @NCKU CSIE

@ Programming Language 2013

Python郭⾄至軒（KuoE0）

KuoE0.tw@gmail.comKuoE0.ch

Latest update: Jan 10, 2014,

Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0)

http://creativecommons.org/licenses/by-sa/3.0/

What is Python?

a programming language

What is Python?

easy to Read

easy to Learneasy to Write

a programming language

PositionMay 2013

PositionMay 2012

Delta in Position Programming Language

1 1 = C2 2 = Java3 4 ↑ Objective-C4 3 ↓ C++5 5 = C#6 6 = PHP7 7 = Visual Basic8 8 = Python9 9 = Perl10 11 ↑ Ruby

http://www.tiobe.com/index.php/content/paperinfo/tpci/index.html

Top Language in TIOBE

Javascript

Python

Objective-C

0% 5% 10% 15% 20% 25%

Top Languages in Github

https://github.com/languages

Javascript

Python

Objective-C

0% 5% 10% 15% 20% 25%

Top Languages in Github

https://github.com/languages

What does the logo mean?

界 Kingdom 動物界 Animalia

⾨門 Phylum 脊索動物⾨門 Chordata

綱 Class 爬蟲科 Reptilia

⺫⽬目 Order 有鱗⺫⽬目 Squamata

科 Family 蟒科 Pythonidae

屬 Genus 蟒屬 Python

http://wallpapers.free-review.net/15__Tree_python.htm

More About Python...

Interpreted Language

Do not need to compile!

Compiled Language

compiler execute

Interpreted Language

execute

But, interpret in execution time.

And, it would be slow...

Object-Oriented Language

Everything in Python is object!

number

function

string

listObject

number

function

string

listObject

overloading

polymorphism

inheritance

multiple inheritance

Imperative Programming

Generic Programming

Functional Programming

Philosophy

There should be one—and preferably only one—obvious way to do it.

Philosophy

Zen of Python

$ $ python -ic “”

Zen of Python

$ $ python -ic “”$ python -ic “”>>>

Zen of Python

$ $ python -ic “”$ python -ic “”>>>$ python -ic “”>>> import this

Zen of Python

$ $ python -ic “”$ python -ic “”>>>$ python -ic “”>>> import this$ python -ic “”>>> import thisThe Zen of Python, by Tim Peters

Beautiful is better than ugly.Explicit is better than implicit.Simple is better than complex.Complex is better than complicated.Flat is better than nested.Sparse is better than dense.Readability counts.Special cases aren't special enough to

>>> import thisThe Zen of Python, by Tim Peters

Beautiful is better than ugly.Explicit is better than implicit.Simple is better than complex.Complex is better than complicated.Flat is better than nested.Sparse is better than dense.Readability counts.Special cases aren't special enough to break the rules.

The Zen of Python, by Tim Peters

Beautiful is better than ugly.Explicit is better than implicit.Simple is better than complex.Complex is better than complicated.Flat is better than nested.Sparse is better than dense.Readability counts.Special cases aren't special enough to break the rules.Although practicality beats purity.

Beautiful is better than ugly.Explicit is better than implicit.Simple is better than complex.Complex is better than complicated.Flat is better than nested.Sparse is better than dense.Readability counts.Special cases aren't special enough to break the rules.Although practicality beats purity.Errors should never pass silently.

Beautiful is better than ugly.Explicit is better than implicit.Simple is better than complex.Complex is better than complicated.Flat is better than nested.Sparse is better than dense.Readability counts.Special cases aren't special enough to break the rules.Although practicality beats purity.Errors should never pass silently.Unless explicitly silenced.

Explicit is better than implicit.Simple is better than complex.Complex is better than complicated.Flat is better than nested.Sparse is better than dense.Readability counts.Special cases aren't special enough to break the rules.Although practicality beats purity.Errors should never pass silently.Unless explicitly silenced.In the face of ambiguity, refuse the

Simple is better than complex.Complex is better than complicated.Flat is better than nested.Sparse is better than dense.Readability counts.Special cases aren't special enough to break the rules.Although practicality beats purity.Errors should never pass silently.Unless explicitly silenced.In the face of ambiguity, refuse the temptation to guess.

Complex is better than complicated.Flat is better than nested.Sparse is better than dense.Readability counts.Special cases aren't special enough to break the rules.Although practicality beats purity.Errors should never pass silently.Unless explicitly silenced.In the face of ambiguity, refuse the temptation to guess.There should be one-- and preferably only

Flat is better than nested.Sparse is better than dense.Readability counts.Special cases aren't special enough to break the rules.Although practicality beats purity.Errors should never pass silently.Unless explicitly silenced.In the face of ambiguity, refuse the temptation to guess.There should be one-- and preferably only one --obvious way to do it.

Sparse is better than dense.Readability counts.Special cases aren't special enough to break the rules.Although practicality beats purity.Errors should never pass silently.Unless explicitly silenced.In the face of ambiguity, refuse the temptation to guess.There should be one-- and preferably only one --obvious way to do it.Although that way may not be obvious at

Readability counts.Special cases aren't special enough to break the rules.Although practicality beats purity.Errors should never pass silently.Unless explicitly silenced.In the face of ambiguity, refuse the temptation to guess.There should be one-- and preferably only one --obvious way to do it.Although that way may not be obvious at first unless you're Dutch.

Special cases aren't special enough to break the rules.Although practicality beats purity.Errors should never pass silently.Unless explicitly silenced.In the face of ambiguity, refuse the temptation to guess.There should be one-- and preferably only one --obvious way to do it.Although that way may not be obvious at first unless you're Dutch.Now is better than never.

break the rules.Although practicality beats purity.Errors should never pass silently.Unless explicitly silenced.In the face of ambiguity, refuse the temptation to guess.There should be one-- and preferably only one --obvious way to do it.Although that way may not be obvious at first unless you're Dutch.Now is better than never.Although never is often better than *right*

Although practicality beats purity.Errors should never pass silently.Unless explicitly silenced.In the face of ambiguity, refuse the temptation to guess.There should be one-- and preferably only one --obvious way to do it.Although that way may not be obvious at first unless you're Dutch.Now is better than never.Although never is often better than *right* now.

Errors should never pass silently.Unless explicitly silenced.In the face of ambiguity, refuse the temptation to guess.There should be one-- and preferably only one --obvious way to do it.Although that way may not be obvious at first unless you're Dutch.Now is better than never.Although never is often better than *right* now.If the implementation is hard to explain,

Unless explicitly silenced.In the face of ambiguity, refuse the temptation to guess.There should be one-- and preferably only one --obvious way to do it.Although that way may not be obvious at first unless you're Dutch.Now is better than never.Although never is often better than *right* now.If the implementation is hard to explain, it's a bad idea.

In the face of ambiguity, refuse the temptation to guess.There should be one-- and preferably only one --obvious way to do it.Although that way may not be obvious at first unless you're Dutch.Now is better than never.Although never is often better than *right* now.If the implementation is hard to explain, it's a bad idea.If the implementation is easy to explain,

temptation to guess.There should be one-- and preferably only one --obvious way to do it.Although that way may not be obvious at first unless you're Dutch.Now is better than never.Although never is often better than *right* now.If the implementation is hard to explain, it's a bad idea.If the implementation is easy to explain, it may be a good idea.

There should be one-- and preferably only one --obvious way to do it.Although that way may not be obvious at first unless you're Dutch.Now is better than never.Although never is often better than *right* now.If the implementation is hard to explain, it's a bad idea.If the implementation is easy to explain, it may be a good idea.Namespaces are one honking great idea --

one --obvious way to do it.Although that way may not be obvious at first unless you're Dutch.Now is better than never.Although never is often better than *right* now.If the implementation is hard to explain, it's a bad idea.If the implementation is easy to explain, it may be a good idea.Namespaces are one honking great idea -- let's do more of those!

Although that way may not be obvious at first unless you're Dutch.Now is better than never.Although never is often better than *right* now.If the implementation is hard to explain, it's a bad idea.If the implementation is easy to explain, it may be a good idea.Namespaces are one honking great idea -- let's do more of those!>>>

Zen of Python

Current Situation

Python 2.x Python 3.x

Current Situation

Coexist!

Current Situation

Coexist!

Current Situation

Coexist!

backwards-incompatible

2.7.x is the latest version under development

more 3-party library 2to3.py

built-in on many OS more supported unicode

the past in someday the future in someday

http://www.ibm.com/developerworks/cn/linux/l-python3-1/

Python 3 的新特性

Python 2.x

Python 2.xToday, Let’s Talk About

Environment

For Unix-like OS User,

Python 2.x is Built-in!

Environment

For Windows User,

Download Fromhttp://www.python.org/download/

if you want to launch Python in command line, add the path of Python binary file into PATH variable.

Check Version of Python

Check Version of Python$ python --version

Check Version of Python$ python --version$ python --versionPython 2.7.5

2.7.5 is released on May 15, 2013

$ $ python

$ $ python$ pythonPython 2.7.5 (default, May 20 2013, 23:41:46) [GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>>

$ pythonPython 2.7.5 (default, May 20 2013, 23:41:46) [GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>>

Interactive Shell

$ $ python

Interactive Shell

prompt

Interactive Shell

prompt

means that your turn!

Interactive Shell

$$ python

Interactive Shell

$$ python$ pythonPython 2.7.5 (default, May 20 2013, 23:41:46) [GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>>

Interactive Shell

$ pythonPython 2.7.5 (default, May 20 2013, 23:41:46) [GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>> 1 + 2 + 3

Interactive Shell

$ pythonPython 2.7.5 (default, May 20 2013, 23:41:46) [GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>> 1 + 2 + 36>>>

Interactive Shell

$ pythonPython 2.7.5 (default, May 20 2013, 23:41:46) [GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>> 1 + 2 + 36>>> “Hello World”

Interactive Shell

$ pythonPython 2.7.5 (default, May 20 2013, 23:41:46) [GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>> 1 + 2 + 36>>> “Hello World”‘Hello World’>>>

Interactive Shell

$ pythonPython 2.7.5 (default, May 20 2013, 23:41:46) [GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>> 1 + 2 + 36>>> “Hello World”‘Hello World’>>> x = 100

Interactive Shell

Python 2.7.5 (default, May 20 2013, 23:41:46) [GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>> 1 + 2 + 36>>> “Hello World”‘Hello World’>>> x = 100>>>

Interactive Shell

Python 2.7.5 (default, May 20 2013, 23:41:46) [GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>> 1 + 2 + 36>>> “Hello World”‘Hello World’>>> x = 100>>> y = 200

Interactive Shell

23:41:46) [GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>> 1 + 2 + 36>>> “Hello World”‘Hello World’>>> x = 100>>> y = 200>>>

Interactive Shell

23:41:46) [GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>> 1 + 2 + 36>>> “Hello World”‘Hello World’>>> x = 100>>> y = 200>>> x + y

Interactive Shell

(clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>> 1 + 2 + 36>>> “Hello World”‘Hello World’>>> x = 100>>> y = 200>>> x + y300>>>

Interactive Shell

(clang-425.0.28)] on darwinType "help", "copyright", "credits" or "license" for more information.>>> 1 + 2 + 36>>> “Hello World”‘Hello World’>>> x = 100>>> y = 200>>> x + y300>>> for i in range(5):

Interactive Shell

Type "help", "copyright", "credits" or "license" for more information.>>> 1 + 2 + 36>>> “Hello World”‘Hello World’>>> x = 100>>> y = 200>>> x + y300>>> for i in range(5):...

Interactive Shell

Type "help", "copyright", "credits" or "license" for more information.>>> 1 + 2 + 36>>> “Hello World”‘Hello World’>>> x = 100>>> y = 200>>> x + y300>>> for i in range(5):... print i

Interactive Shell

"license" for more information.>>> 1 + 2 + 36>>> “Hello World”‘Hello World’>>> x = 100>>> y = 200>>> x + y300>>> for i in range(5):... print i...

Interactive Shell

>>> y = 200>>> x + y300>>> for i in range(5):... print i...01234>>>

Interactive Shell

>>> y = 200>>> x + y300>>> for i in range(5):... print i...01234>>> exit()

Interactive Shell

>>> y = 200>>> x + y300>>> for i in range(5):... print i...01234>>> exit()

>>> x + y300>>> for i in range(5):... print i...01234>>> exit()$

Interactive Shell

Hello World!

if __name__ == “__main__”: print “Hello World!”

helloworld.py

Hello World!

Hello World!$ python helloworld.py

Hello World!$ python helloworld.py$ python helloworld.pyHello World!$

A Python Code

A Python Codedef mul(x, y): ret = x * y return ret

for i in range(10)[2:]: for j in range(10)[1:]: print "{0} x {1} = {2}".format(i, j, mul(i, j))

9x9table.py

script languagedef mul(x, y): ret = x * y return ret

no specified entry point

script language

script language$ python 9x9table.py

script language$ python 9x9table.py$ python 9x9table.py2 x 1 = 22 x 2 = 42 x 3 = 62 x 4 = 82 x 5 = 102 x 6 = 122 x 7 = 142 x 8 = 162 x 9 = 183 x 1 = 33 x 2 = 63 x 3 = 9

2 x 1 = 22 x 2 = 42 x 3 = 62 x 4 = 82 x 5 = 102 x 6 = 122 x 7 = 142 x 8 = 162 x 9 = 183 x 1 = 33 x 2 = 63 x 3 = 93 x 4 = 12

2 x 2 = 42 x 3 = 62 x 4 = 82 x 5 = 102 x 6 = 122 x 7 = 142 x 8 = 162 x 9 = 183 x 1 = 33 x 2 = 63 x 3 = 93 x 4 = 123 x 5 = 15

2 x 3 = 62 x 4 = 82 x 5 = 102 x 6 = 122 x 7 = 142 x 8 = 162 x 9 = 183 x 1 = 33 x 2 = 63 x 3 = 93 x 4 = 123 x 5 = 153 x 6 = 18

2 x 4 = 82 x 5 = 102 x 6 = 122 x 7 = 142 x 8 = 162 x 9 = 183 x 1 = 33 x 2 = 63 x 3 = 93 x 4 = 123 x 5 = 153 x 6 = 183 x 7 = 21

2 x 5 = 102 x 6 = 122 x 7 = 142 x 8 = 162 x 9 = 183 x 1 = 33 x 2 = 63 x 3 = 93 x 4 = 123 x 5 = 153 x 6 = 183 x 7 = 213 x 8 = 24

2 x 6 = 122 x 7 = 142 x 8 = 162 x 9 = 183 x 1 = 33 x 2 = 63 x 3 = 93 x 4 = 123 x 5 = 153 x 6 = 183 x 7 = 213 x 8 = 243 x 9 = 27

2 x 7 = 142 x 8 = 162 x 9 = 183 x 1 = 33 x 2 = 63 x 3 = 93 x 4 = 123 x 5 = 153 x 6 = 183 x 7 = 213 x 8 = 243 x 9 = 274 x 1 = 4

2 x 8 = 162 x 9 = 183 x 1 = 33 x 2 = 63 x 3 = 93 x 4 = 123 x 5 = 153 x 6 = 183 x 7 = 213 x 8 = 243 x 9 = 274 x 1 = 44 x 2 = 8

2 x 9 = 183 x 1 = 33 x 2 = 63 x 3 = 93 x 4 = 123 x 5 = 153 x 6 = 183 x 7 = 213 x 8 = 243 x 9 = 274 x 1 = 44 x 2 = 84 x 3 = 12

3 x 1 = 33 x 2 = 63 x 3 = 93 x 4 = 123 x 5 = 153 x 6 = 183 x 7 = 213 x 8 = 243 x 9 = 274 x 1 = 44 x 2 = 84 x 3 = 124 x 4 = 16

3 x 2 = 63 x 3 = 93 x 4 = 123 x 5 = 153 x 6 = 183 x 7 = 213 x 8 = 243 x 9 = 274 x 1 = 44 x 2 = 84 x 3 = 124 x 4 = 164 x 5 = 20

3 x 3 = 93 x 4 = 123 x 5 = 153 x 6 = 183 x 7 = 213 x 8 = 243 x 9 = 274 x 1 = 44 x 2 = 84 x 3 = 124 x 4 = 164 x 5 = 204 x 6 = 24

3 x 4 = 123 x 5 = 153 x 6 = 183 x 7 = 213 x 8 = 243 x 9 = 274 x 1 = 44 x 2 = 84 x 3 = 124 x 4 = 164 x 5 = 204 x 6 = 244 x 7 = 28

3 x 5 = 153 x 6 = 183 x 7 = 213 x 8 = 243 x 9 = 274 x 1 = 44 x 2 = 84 x 3 = 124 x 4 = 164 x 5 = 204 x 6 = 244 x 7 = 284 x 8 = 32

3 x 6 = 183 x 7 = 213 x 8 = 243 x 9 = 274 x 1 = 44 x 2 = 84 x 3 = 124 x 4 = 164 x 5 = 204 x 6 = 244 x 7 = 284 x 8 = 324 x 9 = 36

3 x 7 = 213 x 8 = 243 x 9 = 274 x 1 = 44 x 2 = 84 x 3 = 124 x 4 = 164 x 5 = 204 x 6 = 244 x 7 = 284 x 8 = 324 x 9 = 365 x 1 = 5

3 x 8 = 243 x 9 = 274 x 1 = 44 x 2 = 84 x 3 = 124 x 4 = 164 x 5 = 204 x 6 = 244 x 7 = 284 x 8 = 324 x 9 = 365 x 1 = 55 x 2 = 10

3 x 9 = 274 x 1 = 44 x 2 = 84 x 3 = 124 x 4 = 164 x 5 = 204 x 6 = 244 x 7 = 284 x 8 = 324 x 9 = 365 x 1 = 55 x 2 = 105 x 3 = 15

4 x 1 = 44 x 2 = 84 x 3 = 124 x 4 = 164 x 5 = 204 x 6 = 244 x 7 = 284 x 8 = 324 x 9 = 365 x 1 = 55 x 2 = 105 x 3 = 155 x 4 = 20

4 x 2 = 84 x 3 = 124 x 4 = 164 x 5 = 204 x 6 = 244 x 7 = 284 x 8 = 324 x 9 = 365 x 1 = 55 x 2 = 105 x 3 = 155 x 4 = 205 x 5 = 25

4 x 3 = 124 x 4 = 164 x 5 = 204 x 6 = 244 x 7 = 284 x 8 = 324 x 9 = 365 x 1 = 55 x 2 = 105 x 3 = 155 x 4 = 205 x 5 = 255 x 6 = 30

4 x 4 = 164 x 5 = 204 x 6 = 244 x 7 = 284 x 8 = 324 x 9 = 365 x 1 = 55 x 2 = 105 x 3 = 155 x 4 = 205 x 5 = 255 x 6 = 305 x 7 = 35

4 x 5 = 204 x 6 = 244 x 7 = 284 x 8 = 324 x 9 = 365 x 1 = 55 x 2 = 105 x 3 = 155 x 4 = 205 x 5 = 255 x 6 = 305 x 7 = 355 x 8 = 40

4 x 6 = 244 x 7 = 284 x 8 = 324 x 9 = 365 x 1 = 55 x 2 = 105 x 3 = 155 x 4 = 205 x 5 = 255 x 6 = 305 x 7 = 355 x 8 = 405 x 9 = 45

4 x 7 = 284 x 8 = 324 x 9 = 365 x 1 = 55 x 2 = 105 x 3 = 155 x 4 = 205 x 5 = 255 x 6 = 305 x 7 = 355 x 8 = 405 x 9 = 456 x 1 = 6

4 x 8 = 324 x 9 = 365 x 1 = 55 x 2 = 105 x 3 = 155 x 4 = 205 x 5 = 255 x 6 = 305 x 7 = 355 x 8 = 405 x 9 = 456 x 1 = 66 x 2 = 12

4 x 9 = 365 x 1 = 55 x 2 = 105 x 3 = 155 x 4 = 205 x 5 = 255 x 6 = 305 x 7 = 355 x 8 = 405 x 9 = 456 x 1 = 66 x 2 = 126 x 3 = 18

5 x 1 = 55 x 2 = 105 x 3 = 155 x 4 = 205 x 5 = 255 x 6 = 305 x 7 = 355 x 8 = 405 x 9 = 456 x 1 = 66 x 2 = 126 x 3 = 186 x 4 = 24

5 x 2 = 105 x 3 = 155 x 4 = 205 x 5 = 255 x 6 = 305 x 7 = 355 x 8 = 405 x 9 = 456 x 1 = 66 x 2 = 126 x 3 = 186 x 4 = 246 x 5 = 30

5 x 3 = 155 x 4 = 205 x 5 = 255 x 6 = 305 x 7 = 355 x 8 = 405 x 9 = 456 x 1 = 66 x 2 = 126 x 3 = 186 x 4 = 246 x 5 = 306 x 6 = 36

5 x 4 = 205 x 5 = 255 x 6 = 305 x 7 = 355 x 8 = 405 x 9 = 456 x 1 = 66 x 2 = 126 x 3 = 186 x 4 = 246 x 5 = 306 x 6 = 366 x 7 = 42

5 x 5 = 255 x 6 = 305 x 7 = 355 x 8 = 405 x 9 = 456 x 1 = 66 x 2 = 126 x 3 = 186 x 4 = 246 x 5 = 306 x 6 = 366 x 7 = 426 x 8 = 48

5 x 6 = 305 x 7 = 355 x 8 = 405 x 9 = 456 x 1 = 66 x 2 = 126 x 3 = 186 x 4 = 246 x 5 = 306 x 6 = 366 x 7 = 426 x 8 = 486 x 9 = 54

5 x 7 = 355 x 8 = 405 x 9 = 456 x 1 = 66 x 2 = 126 x 3 = 186 x 4 = 246 x 5 = 306 x 6 = 366 x 7 = 426 x 8 = 486 x 9 = 547 x 1 = 7

5 x 8 = 405 x 9 = 456 x 1 = 66 x 2 = 126 x 3 = 186 x 4 = 246 x 5 = 306 x 6 = 366 x 7 = 426 x 8 = 486 x 9 = 547 x 1 = 77 x 2 = 14

5 x 9 = 456 x 1 = 66 x 2 = 126 x 3 = 186 x 4 = 246 x 5 = 306 x 6 = 366 x 7 = 426 x 8 = 486 x 9 = 547 x 1 = 77 x 2 = 147 x 3 = 21

6 x 1 = 66 x 2 = 126 x 3 = 186 x 4 = 246 x 5 = 306 x 6 = 366 x 7 = 426 x 8 = 486 x 9 = 547 x 1 = 77 x 2 = 147 x 3 = 217 x 4 = 28

6 x 2 = 126 x 3 = 186 x 4 = 246 x 5 = 306 x 6 = 366 x 7 = 426 x 8 = 486 x 9 = 547 x 1 = 77 x 2 = 147 x 3 = 217 x 4 = 287 x 5 = 35

6 x 3 = 186 x 4 = 246 x 5 = 306 x 6 = 366 x 7 = 426 x 8 = 486 x 9 = 547 x 1 = 77 x 2 = 147 x 3 = 217 x 4 = 287 x 5 = 357 x 6 = 42

6 x 4 = 246 x 5 = 306 x 6 = 366 x 7 = 426 x 8 = 486 x 9 = 547 x 1 = 77 x 2 = 147 x 3 = 217 x 4 = 287 x 5 = 357 x 6 = 427 x 7 = 49

6 x 5 = 306 x 6 = 366 x 7 = 426 x 8 = 486 x 9 = 547 x 1 = 77 x 2 = 147 x 3 = 217 x 4 = 287 x 5 = 357 x 6 = 427 x 7 = 497 x 8 = 56

6 x 6 = 366 x 7 = 426 x 8 = 486 x 9 = 547 x 1 = 77 x 2 = 147 x 3 = 217 x 4 = 287 x 5 = 357 x 6 = 427 x 7 = 497 x 8 = 567 x 9 = 63

6 x 7 = 426 x 8 = 486 x 9 = 547 x 1 = 77 x 2 = 147 x 3 = 217 x 4 = 287 x 5 = 357 x 6 = 427 x 7 = 497 x 8 = 567 x 9 = 638 x 1 = 8

6 x 8 = 486 x 9 = 547 x 1 = 77 x 2 = 147 x 3 = 217 x 4 = 287 x 5 = 357 x 6 = 427 x 7 = 497 x 8 = 567 x 9 = 638 x 1 = 88 x 2 = 16

6 x 9 = 547 x 1 = 77 x 2 = 147 x 3 = 217 x 4 = 287 x 5 = 357 x 6 = 427 x 7 = 497 x 8 = 567 x 9 = 638 x 1 = 88 x 2 = 168 x 3 = 24

7 x 1 = 77 x 2 = 147 x 3 = 217 x 4 = 287 x 5 = 357 x 6 = 427 x 7 = 497 x 8 = 567 x 9 = 638 x 1 = 88 x 2 = 168 x 3 = 248 x 4 = 32

7 x 2 = 147 x 3 = 217 x 4 = 287 x 5 = 357 x 6 = 427 x 7 = 497 x 8 = 567 x 9 = 638 x 1 = 88 x 2 = 168 x 3 = 248 x 4 = 328 x 5 = 40

7 x 3 = 217 x 4 = 287 x 5 = 357 x 6 = 427 x 7 = 497 x 8 = 567 x 9 = 638 x 1 = 88 x 2 = 168 x 3 = 248 x 4 = 328 x 5 = 408 x 6 = 48

7 x 4 = 287 x 5 = 357 x 6 = 427 x 7 = 497 x 8 = 567 x 9 = 638 x 1 = 88 x 2 = 168 x 3 = 248 x 4 = 328 x 5 = 408 x 6 = 488 x 7 = 56

7 x 5 = 357 x 6 = 427 x 7 = 497 x 8 = 567 x 9 = 638 x 1 = 88 x 2 = 168 x 3 = 248 x 4 = 328 x 5 = 408 x 6 = 488 x 7 = 568 x 8 = 64

7 x 6 = 427 x 7 = 497 x 8 = 567 x 9 = 638 x 1 = 88 x 2 = 168 x 3 = 248 x 4 = 328 x 5 = 408 x 6 = 488 x 7 = 568 x 8 = 648 x 9 = 72

7 x 7 = 497 x 8 = 567 x 9 = 638 x 1 = 88 x 2 = 168 x 3 = 248 x 4 = 328 x 5 = 408 x 6 = 488 x 7 = 568 x 8 = 648 x 9 = 729 x 1 = 9

7 x 8 = 567 x 9 = 638 x 1 = 88 x 2 = 168 x 3 = 248 x 4 = 328 x 5 = 408 x 6 = 488 x 7 = 568 x 8 = 648 x 9 = 729 x 1 = 99 x 2 = 18

7 x 9 = 638 x 1 = 88 x 2 = 168 x 3 = 248 x 4 = 328 x 5 = 408 x 6 = 488 x 7 = 568 x 8 = 648 x 9 = 729 x 1 = 99 x 2 = 189 x 3 = 27

8 x 1 = 88 x 2 = 168 x 3 = 248 x 4 = 328 x 5 = 408 x 6 = 488 x 7 = 568 x 8 = 648 x 9 = 729 x 1 = 99 x 2 = 189 x 3 = 279 x 4 = 36

8 x 2 = 168 x 3 = 248 x 4 = 328 x 5 = 408 x 6 = 488 x 7 = 568 x 8 = 648 x 9 = 729 x 1 = 99 x 2 = 189 x 3 = 279 x 4 = 369 x 5 = 45

8 x 3 = 248 x 4 = 328 x 5 = 408 x 6 = 488 x 7 = 568 x 8 = 648 x 9 = 729 x 1 = 99 x 2 = 189 x 3 = 279 x 4 = 369 x 5 = 459 x 6 = 54

8 x 4 = 328 x 5 = 408 x 6 = 488 x 7 = 568 x 8 = 648 x 9 = 729 x 1 = 99 x 2 = 189 x 3 = 279 x 4 = 369 x 5 = 459 x 6 = 549 x 7 = 63

8 x 5 = 408 x 6 = 488 x 7 = 568 x 8 = 648 x 9 = 729 x 1 = 99 x 2 = 189 x 3 = 279 x 4 = 369 x 5 = 459 x 6 = 549 x 7 = 639 x 8 = 72

8 x 6 = 488 x 7 = 568 x 8 = 648 x 9 = 729 x 1 = 99 x 2 = 189 x 3 = 279 x 4 = 369 x 5 = 459 x 6 = 549 x 7 = 639 x 8 = 729 x 9 = 81

8 x 7 = 568 x 8 = 648 x 9 = 729 x 1 = 99 x 2 = 189 x 3 = 279 x 4 = 369 x 5 = 459 x 6 = 549 x 7 = 639 x 8 = 729 x 9 = 81$

If you need a main function as entry point,

and write all statements after it.

def mul(x, y): ret = x * y return ret

variable

can be used without declaration

variabledef mul(x, y): ret = x * y return ret

can be used without declaration

use whitespace to identify scope

scopedef mul(x, y): ret = x * y return ret

use whitespace to identify scope

You can use

to identify scopes.

You can useone space

two spaces

three spaces

four spaces

lots of spaces

to identify scopes.

You can useone space

two spaces

three spaces

four spaces

lots of spaces

one tab

two tabs

three tabs

four tabs

lots of tabs

to identify scopes.

But, you should unify the style!

Built-in Data Type

None>>>

None>>>>>> None

None>>>>>> None>>> None>>>

Boolean

TrueFalse

Boolean

TrueFalse

>>> >>> 1 == 1

Boolean

TrueFalse

>>> >>> 1 == 1>>> 1 == 1True>>>

Boolean

TrueFalse

>>> >>> 1 == 1>>> 1 == 1True>>>

>>> 1 == 1True>>> 1 != 1

Boolean

TrueFalse

>>> >>> 1 == 1>>> 1 == 1True>>>

>>> 1 == 1True>>> 1 != 1

>>> 1 == 1True>>> 1 != 1False>>>

Boolean

TrueFalse

>>> >>> 1 == 1>>> 1 == 1True>>>

>>> 1 == 1True>>> 1 != 1

>>> 1 == 1True>>> 1 != 1False>>>

>>> 1 == 1True>>> 1 != 1False>>> True

Boolean

TrueFalse

>>> >>> 1 == 1>>> 1 == 1True>>>

>>> 1 == 1True>>> 1 != 1

>>> 1 == 1True>>> 1 != 1False>>>

>>> 1 == 1True>>> 1 != 1False>>> True

>>> 1 == 1True>>> 1 != 1False>>> TrueTrue>>>

Boolean

TrueFalse

>>> >>> 1 == 1>>> 1 == 1True>>>

>>> 1 == 1True>>> 1 != 1

>>> 1 == 1True>>> 1 != 1False>>>

>>> 1 == 1True>>> 1 != 1False>>> True

>>> 1 == 1True>>> 1 != 1False>>> TrueTrue>>> False

Boolean

TrueFalse

>>> >>> 1 == 1>>> 1 == 1True>>>

>>> 1 == 1True>>> 1 != 1

>>> 1 == 1True>>> 1 != 1False>>>

>>> 1 == 1True>>> 1 != 1False>>> True

>>> 1 == 1True>>> 1 != 1False>>> TrueTrue>>> False

True>>> 1 != 1False>>> TrueTrue>>> FalseFalse>>>

Boolean

TrueFalse

Boolean

TrueFalse

upper case>>>

Boolean

TrueFalse

upper case>>> >>> true

Boolean

TrueFalse

upper case>>> >>> true>>> trueTraceback (most recent call last): File "<input>", line 1, in <module>NameError: name 'true' is not defined>>>

Initialization / Conversion

TrueFalse

>>> >>> bool(1)

TrueFalse

>>> >>> bool(1)>>> bool(1)True>>>

TrueFalse

>>> >>> bool(1)>>> bool(1)True>>>

>>> bool(1)True>>> bool(True)

TrueFalse

>>> >>> bool(1)>>> bool(1)True>>>

>>> bool(1)True>>> bool(True)True>>>

TrueFalse

>>> >>> bool(1)>>> bool(1)True>>>

>>> bool(1)True>>> bool(True)True>>> bool()

TrueFalse

>>> >>> bool(1)>>> bool(1)True>>>

>>> bool(1)True>>> bool(True)True>>> bool()

>>> bool(1)True>>> bool(True)True>>> bool()False>>>

Logical Operators

and and

not not

Logical Operators

and and

not not

>>> >>> (1 == 1) and True

Logical Operators

and and

not not

>>> >>> (1 == 1) and True>>> (1 == 1) and TrueTrue>>>

Logical Operators

and and

not not

>>> (1 == 1) and TrueTrue>>> (1 == 1) or False

Logical Operators

and and

not not

>>> (1 == 1) and TrueTrue>>> (1 == 1) or FalseTrue>>>

Logical Operators

and and

not not

>>> (1 == 1) and TrueTrue>>> (1 == 1) or FalseTrue>>> not (1 == 1)

Logical Operators

and and

not not

>>> (1 == 1) and TrueTrue>>> (1 == 1) or FalseTrue>>> not (1 == 1)

>>> (1 == 1) and TrueTrue>>> (1 == 1) or FalseTrue>>> not (1 == 1)False>>>

Numbers

int(integer)

long(long integer)

float(real number)

complex(complex number)

10 10L 100.0 3 + 2j

-789 -789L -21.9 3 - 2j

-0x111 0xFFFFFFFFF 3.20E+10 45j

0x69 -0x12321L -2.00E-08 3e+26j

Initialization / Conversiondata type initial

int int(x)

long long(x)

float float(x)

complex complex(x)complex(x, y)

int int(x)

long long(x)

float float(x)

>>> >>> int(10)

int int(x)

long long(x)

float float(x)

>>> >>> int(10)>>> int(10)10>>>

int int(x)

long long(x)

float float(x)

>>> >>> int(10)>>> int(10)10>>>

>>> int(10)10>>> int(“100”)

int int(x)

long long(x)

float float(x)

>>> >>> int(10)>>> int(10)10>>>

>>> int(10)10>>> int(“100”)

>>> int(10)10>>> int(“100”)100>>>

int int(x)

long long(x)

float float(x)

>>> >>> int(10)>>> int(10)10>>>

>>> int(10)10>>> int(“100”)

>>> int(10)10>>> int(“100”)100>>>

>>> int(10)10>>> int(“100”)100>>> complex(10)

int int(x)

long long(x)

float float(x)

>>> >>> int(10)>>> int(10)10>>>

>>> int(10)10>>> int(“100”)

>>> int(10)10>>> int(“100”)100>>>

>>> int(10)10>>> int(“100”)100>>> complex(10)

>>> int(10)10>>> int(“100”)100>>> complex(10)(10+0j)>>>

int int(x)

long long(x)

float float(x)

>>> >>> int(10)>>> int(10)10>>>

>>> int(10)10>>> int(“100”)

>>> int(10)10>>> int(“100”)100>>>

>>> int(10)10>>> int(“100”)100>>> complex(10)

>>> int(10)10>>> int(“100”)100>>> complex(10)(10+0j)>>>

>>> int(10)10>>> int(“100”)100>>> complex(10)(10+0j)>>> complex(10, 3)

int int(x)

long long(x)

float float(x)

>>> >>> int(10)>>> int(10)10>>>

>>> int(10)10>>> int(“100”)

>>> int(10)10>>> int(“100”)100>>>

>>> int(10)10>>> int(“100”)100>>> complex(10)

>>> int(10)10>>> int(“100”)100>>> complex(10)(10+0j)>>>

10>>> int(“100”)100>>> complex(10)(10+0j)>>> complex(10, 3)(10+3j)>>>

int int(x)

long long(x)

float float(x)

>>> >>> int(10)>>> int(10)10>>>

>>> int(10)10>>> int(“100”)

>>> int(10)10>>> int(“100”)100>>>

>>> int(10)10>>> int(“100”)100>>> complex(10)

>>> int(10)10>>> int(“100”)100>>> complex(10)(10+0j)>>>

10>>> int(“100”)100>>> complex(10)(10+0j)>>> complex(10, 3)(10+3j)>>> complex(“20+5j”)

int int(x)

long long(x)

float float(x)

>>> >>> int(10)>>> int(10)10>>>

>>> int(10)10>>> int(“100”)

>>> int(10)10>>> int(“100”)100>>>

>>> int(10)10>>> int(“100”)100>>> complex(10)

>>> int(10)10>>> int(“100”)100>>> complex(10)(10+0j)>>>

10>>> int(“100”)100>>> complex(10)(10+0j)>>> complex(10, 3)(10+3j)>>> complex(“20+5j”)

100>>> complex(10)(10+0j)>>> complex(10, 3)(10+3j)>>> complex(“20+5j”)(20+5j)>>>

Arithmetic Operators+ addition

- subtraction

* multiplication/ division% modular

** exponential

// floor division

- subtraction

** exponential

// floor division

>>> >>> 2**10

- subtraction

** exponential

// floor division

>>> >>> 2**10>>> 2**101024>>>

- subtraction

** exponential

// floor division

>>> >>> 2**10>>> 2**101024>>>

>>> 2**101024>>> 5.8 // 2

- subtraction

** exponential

// floor division

>>> >>> 2**10>>> 2**101024>>>

>>> 2**101024>>> 5.8 // 2

>>> 2**101024>>> 5.8 // 22.0>>>

Bitwise Operators& and

^ exclusion or>> shift right<< shift left

>>>>>> 3 & 1

>>>>>> 3 & 1>>> 3 & 11>>>

>>> 3 & 11>>> 1 << 10

>>>>>> 3 & 1>>> 3 & 11>>>

>>> 3 & 11>>> 1 << 10

>>> 3 & 11>>> 1 << 101024>>>

>>>>>> 3 & 1>>> 3 & 11>>>

>>> 3 & 11>>> 1 << 10

>>> 3 & 11>>> 1 << 101024>>>

>>> 3 & 11>>> 1 << 101024>>> ~0

>>>>>> 3 & 1>>> 3 & 11>>>

>>> 3 & 11>>> 1 << 10

>>> 3 & 11>>> 1 << 101024>>>

>>> 3 & 11>>> 1 << 101024>>> ~0

>>> 3 & 11>>> 1 << 101024>>> ~0-1>>>

Comparison Operators> greater than

>= greater than or equal to

< less than<= less than or equal to == equal to

!= not equal to

String

Contents are surrounded by single quote or double quote.

String

>>>>>> “Hello World”

String

>>>>>> “Hello World”>>> “Hello World”‘Hello World’>>>

String

>>> “Hello World!”‘Hello World’>>> ‘Hello World!’

String

>>> “Hello World!”‘Hello World’>>> ‘Hello World!’

>>> “Hello World!”‘Hello World’>>> ‘Hello World!’‘Hello World’>>>

Cross-line String

Contents are surrounded by three single quotes or three double quotes.

Cross-line String

>>> >>> “““Hello

Cross-line String

>>> >>> “““Hello>>> “““Hello...

Cross-line String

>>> >>> “““Hello>>> “““Hello... >>> “““Hello... World!”””

Cross-line String

>>> >>> “““Hello>>> “““Hello... >>> “““Hello... World!”””>>> “““Hello... World!”””‘Hello\nWorld!’>>>

Cross-line String

>>> “““Hello... World!”””‘Hello\nWorld!’>>> x = “““Hello

Cross-line String

>>> “““Hello... World!”””‘Hello\nWorld!’>>> x = “““Hello...

Cross-line String

>>> “““Hello... World!”””‘Hello\nWorld!’>>> x = “““Hello... World!”””

Cross-line String

>>> “““Hello... World!”””‘Hello\nWorld!’>>> x = “““Hello... World!”””>>>

Cross-line String

>>> “““Hello... World!”””‘Hello\nWorld!’>>> x = “““Hello... World!”””>>> print x

Cross-line String

>>> “““Hello... World!”””‘Hello\nWorld!’>>> x = “““Hello... World!”””>>> print x

... World!”””‘Hello\nWorld!’>>> x = “““Hello... World!”””>>> print xHelloWorld!>>>

>>> >>> str(“I’m string”)

>>> >>> str(“I’m string”)>>> str(“I’m string”)“I’m string”>>>

>>> str(“I’m string”)“I’m string”>>> str(100)

>>> str(“I’m string”)“I’m string”>>> str(100)‘100’>>>

>>> str(“I’m string”)“I’m string”>>> str(100)‘100’>>> str(complex(10, 3))

>>> str(“I’m string”)“I’m string”>>> str(100)‘100’>>> str(complex(10, 3))‘(10+3j)’>>>

Operators

+ concatenate

* repeat

>>>>>> x = “abc”

Operators

+ concatenate

* repeat

>>>>>> x = “abc”>>> x = “abc”>>>

Operators

+ concatenate

* repeat

>>>>>> x = “abc”>>> x = “abc”>>> >>> x = “abc”>>> ‘(’ + x + ‘)’

Operators

+ concatenate

* repeat

>>>>>> x = “abc”>>> x = “abc”>>> >>> x = “abc”>>> ‘(’ + x + ‘)’>>> x = “abc”>>> ‘(’ + x + ‘)’‘(abc)’>>>

Operators

+ concatenate

* repeat

>>> x = “abc”>>> ‘(’ + x + ‘)’‘(abc)’>>> x * 3

Operators

+ concatenate

* repeat

>>> x = “abc”>>> ‘(’ + x + ‘)’‘(abc)’>>> x * 3

>>> x = “abc”>>> ‘(’ + x + ‘)’‘(abc)’>>> x * 3‘abcabcabc’>>>

Operators

+ concatenate

* repeat

>>> x = “abc”>>> ‘(’ + x + ‘)’‘(abc)’>>> x * 3

>>> x = “abc”>>> ‘(’ + x + ‘)’‘(abc)’>>> x * 3‘abcabcabc’>>> ‘(’ + x * 3 + ‘)’

Operators

+ concatenate

* repeat

>>> x = “abc”>>> ‘(’ + x + ‘)’‘(abc)’>>> x * 3

>>> x = ‘abc’>>> ‘(’ + x + ‘)’‘(abc)’>>> x * 3‘abcabcabc’>>> ‘(’ + x * 3 + ‘)’‘(abcabcabc)’>>>

Operators

+ concatenate

* repeat

>>> x = “abc”>>> ‘(’ + x + ‘)’‘(abc)’>>> x * 3

>>> x = ‘abc’>>> ‘(’ + x + ‘)’‘(abc)’>>> x * 3‘abcabcabc’>>> ‘(’ + x * 3 + ‘)’‘(abcabcabc)’>>> (x + ‘d’) * 3

Operators

+ concatenate

* repeat

>>> x = “abc”>>> ‘(’ + x + ‘)’‘(abc)’>>> x * 3

>>> x = ‘abc’>>> ‘(’ + x + ‘)’‘(abc)’>>> x * 3‘abcabcabc’>>> ‘(’ + x * 3 + ‘)’‘(abcabcabc)’>>> (x + ‘d’) * 3

‘(abc)’>>> x * 3‘abcabcabc’>>> ‘(’ + x * 3 + ‘)’‘(abcabcabc)’>>> (x + ‘d’) * 3‘abcdabcdabcd’>>>

Operators

+ concatenate

* repeat

Access Character

>>>>>> x = ‘0123456789’

Access Character

>>>>>> x = ‘0123456789’>>> x = ‘0123456789’>>>

Access Character

>>>>>> x = ‘0123456789’>>> x = ‘0123456789’>>> >>> x = ‘0123456789’>>> x[1]

Access Character

>>>>>> x = ‘0123456789’>>> x = ‘0123456789’>>> >>> x = ‘0123456789’>>> x[1]>>> x = ‘0123456789’>>> x[1]‘1’>>>

Access Character

>>>>>> x = ‘0123456789’>>> x = ‘0123456789’>>> >>> x = ‘0123456789’>>> x[1]>>> x = ‘0123456789’>>> x[1]‘1’>>>

>>> x = ‘0123456789’>>> x[1]‘1’>>> x[1] = ‘0’

Access Character

>>>>>> x = ‘0123456789’>>> x = ‘0123456789’>>> >>> x = ‘0123456789’>>> x[1]>>> x = ‘0123456789’>>> x[1]‘1’>>>

>>> x = ‘0123456789’>>> x[1]‘1’>>> x[1] = ‘0’

>>> x = ‘0123456789’>>> x[1]‘1’>>> x[1] = ‘0’>>>

Access Character

>>>>>> x = ‘0123456789’>>> x = ‘0123456789’>>> >>> x = ‘0123456789’>>> x[1]>>> x = ‘0123456789’>>> x[1]‘1’>>>

>>> x = ‘0123456789’>>> x[1]‘1’>>> x[1] = ‘0’

>>> x = ‘0123456789’>>> x[1]‘1’>>> x[1] = ‘0’>>>

>>> x = ‘0123456789’>>> x[1]‘1’>>> x[1] = ‘0’>>> x

Access Character

>>>>>> x = ‘0123456789’>>> x = ‘0123456789’>>> >>> x = ‘0123456789’>>> x[1]>>> x = ‘0123456789’>>> x[1]‘1’>>>

>>> x = ‘0123456789’>>> x[1]‘1’>>> x[1] = ‘0’

>>> x = ‘0123456789’>>> x[1]‘1’>>> x[1] = ‘0’>>>

>>> x = ‘0123456789’>>> x[1]‘1’>>> x[1] = ‘0’>>> x

>>> x = ‘0123456789’>>> x[1]‘1’>>> x[1] = ‘0’>>> x‘0023456789’>>>

Access Character

substring

[start:end(:step)]

substring

[start:end(:step)]

[0:length(:1)]

default value

>>>>>> x = “0123456789”

substring

[start:end(:step)]

[0:length(:1)]

default value

>>>>>> x = “0123456789”>>> x = “0123456789”>>>

substring

[start:end(:step)]

[0:length(:1)]

default value

>>>>>> x = “0123456789”>>> x = “0123456789”>>>>>> x = “0123456789”>>> x[::]

substring

[start:end(:step)]

[0:length(:1)]

default value

>>>>>> x = “0123456789”>>> x = “0123456789”>>>>>> x = “0123456789”>>> x[::]>>> x = “0123456789”>>> x[::]‘0123456789’>>>

substring

[start:end(:step)]

[0:length(:1)]

default value

>>>>>> x = “0123456789”>>> x = “0123456789”>>>>>> x = “0123456789”>>> x[::]>>> x = “0123456789”>>> x[::]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]

substring

[start:end(:step)]

[0:length(:1)]

default value

>>>>>> x = “0123456789”>>> x = “0123456789”>>>>>> x = “0123456789”>>> x[::]>>> x = “0123456789”>>> x[::]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>>

substring

[start:end(:step)]

[0:length(:1)]

default value

>>>>>> x = “0123456789”>>> x = “0123456789”>>>>>> x = “0123456789”>>> x[::]>>> x = “0123456789”>>> x[::]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]

substring

[start:end(:step)]

[0:length(:1)]

default value

>>>>>> x = “0123456789”>>> x = “0123456789”>>>>>> x = “0123456789”>>> x[::]>>> x = “0123456789”>>> x[::]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>>

substring

[start:end(:step)]

[0:length(:1)]

default value

>>>>>> x = “0123456789”>>> x = “0123456789”>>>>>> x = “0123456789”>>> x[::]>>> x = “0123456789”>>> x[::]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]

substring

[start:end(:step)]

[0:length(:1)]

default value

>>>>>> x = “0123456789”>>> x = “0123456789”>>>>>> x = “0123456789”>>> x[::]>>> x = “0123456789”>>> x[::]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]

‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]‘12345678’>>>

substring

[start:end(:step)]

[0:length(:1)]

default value

>>>>>> x = “0123456789”>>> x = “0123456789”>>>>>> x = “0123456789”>>> x[::]>>> x = “0123456789”>>> x[::]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]

‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]‘12345678’>>>

‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]‘12345678’>>> x[::2]

substring

[start:end(:step)]

[0:length(:1)]

default value

>>>>>> x = “0123456789”>>> x = “0123456789”>>>>>> x = “0123456789”>>> x[::]>>> x = “0123456789”>>> x[::]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]

‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]‘12345678’>>>

‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]‘12345678’>>> x[::2]

‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]‘12345678’>>> x[::2]‘02468’>>>

substring

[start:end(:step)]

[0:length(:1)]

default value

>>>>>> x = “0123456789”>>> x = “0123456789”>>>>>> x = “0123456789”>>> x[::]>>> x = “0123456789”>>> x[::]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>>

>>> x = “0123456789”>>> x[::]‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]

‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]‘12345678’>>>

‘0123456789’>>> x[:]‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]‘12345678’>>> x[::2]

‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]‘12345678’>>> x[::2]‘02468’>>>

‘0123456789’>>> x[1:4]‘123’>>> x[1:-1]‘12345678’>>> x[::2]‘02468’>>> x[::-1]