Python Standard Library

Chapter 1. Core Modules

“Since the functions in the C runtime library are not part of the Win32 API, we believe the number of applications that will be affected by this bug to be very limited.”

—Microsoft, January 1999

Introduction

Python’s standard library covers a wide range of modules. It includes everything from modules that are as much a part of the Python language as the types and statements defined by the language specification, to obscure modules that are probably useful only to a small number of programs.

This chapter describes a number of fundamental standard library modules. Any larger Python program is likely to use most of these modules, either directly or indirectly.

Built-in Functions and Exceptions

The following two modules are even more basic than all other modules combined: the _ _builtin_ _ module, which defines built-in functions (like len, int, and range), and the exceptions module, which defines all built-in exceptions.

Python imports both modules when it starts up, and makes their content available for all programs.

Operating System Interface Modules

There are a number of modules modeled after the POSIX standard API and the standard C library that provide platform-independent interfaces to the underlying operating system.

The modules in this group include os, which provides file and process operations, os.path, which offers a platform-independent way to pull apart and put together filenames, and time, which provides functions to work with dates and times. ...