Standard LibraryΒΆ
- Python contains hundreds of standard library modules performing a variety of common tasks.
- Use standard functions over custom code when possible for clarity, portability and (usually) speed.
- Common standard modules include
math
,random
,time
,os
andsys
. Import them - Even standard modules must be imported before use.
- Some very common functions (e.g., file I/O) are built-in functions (no import needed).
>>> import math
>>> math.sqrt(2.0)
1.4142135623730951
>>> f = open("file.txt", "r")
>>> type(f)
<type 'file'>
>>> lines = f.readlines() # Reads file into list of strings.
>>> ...