Introduction

In Python, a module is simply a file which contains Python code and which can be imported into some other program. Thus, if you have a collection of functions which you'd like to use in other python programs, you can simply put them all in one file, say myfunctions.py, and use the import statement to make those functions available to you. If your module is located in your working directory, Python will always find it. Otherwise, it must be located in Python's search path. You can view the search path with the following Python statements:

import sys
sys.path

Since sys.path is just a list, you can append the names of other directories to search onto this list before using an import statement, to allow you to access modules which are not on the search path. But if you keep your modules in one location, a more useful approach may be to set the PYTHONPATH environmental variable to that location in the appropriate startup file for your operating system. That way, all the Python programs you run will be able to use your modules.