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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 and
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).


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.


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.

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