Skip to ContentGo to accessibility pageKeyboard shortcuts menu
OpenStax Logo

Highlights from this chapter include:

  • Programs can be organized into multiple .py files (modules). The import keyword allows a program to use functions defined in another .py file.
  • The from keyword can be used to import specific functions from a module. However, programs should avoid importing (or defining) multiple functions with the same name.
  • Modules often include the line if __name__ == "__main__" to prevent code from running as a side effect when the module is imported by other programs.
  • When working in a shell, the help() function can be used to look up the documentation for a module. The documentation is generated from the docstrings.
  • Python comes with over 200 built-in modules and hundreds of thousands of third-party modules. Programmers can search for modules on docs.python.org and pypi.org.
Statement Description

import module

Imports a module for use in another program.

from module import function

Imports a specific function from a module.

if __name__ == "__main__":

A line of code found at the end of many modules. This statement indicates what code to run if the module is executed as a program (in other words, what code not to run if this module is imported by another program).

help(module_name)

Shows the documentation for the given module. The documentation includes the module's docstring, followed by a list of functions defined in the module, followed by a list of global variables assigned in the module, followed by the module's file name.

help(function_name)

Shows the docstring for the given function.

date(2023, 2, 14)

Creates a date object representing February 14, 2023.
Requires: from datetime import date.

Table 7.3 Chapter 7 reference.
Citation/Attribution

This book may not be used in the training of large language models or otherwise be ingested into large language models or generative AI offerings without OpenStax's permission.

Want to cite, share, or modify this book? This book uses the Creative Commons Attribution License and you must attribute OpenStax.

Attribution information
  • If you are redistributing all or part of this book in a print format, then you must include on every physical page the following attribution:
    Access for free at https://openstax.org/books/introduction-python-programming/pages/1-introduction
  • If you are redistributing all or part of this book in a digital format, then you must include on every digital page view the following attribution:
    Access for free at https://openstax.org/books/introduction-python-programming/pages/1-introduction
Citation information

© Feb 26, 2024 OpenStax. Textbook content produced by OpenStax is licensed under a Creative Commons Attribution License . The OpenStax name, OpenStax logo, OpenStax book covers, OpenStax CNX name, and OpenStax CNX logo are not subject to the Creative Commons license and may not be reproduced without the prior and express written consent of Rice University.