Python Learning note five: modules and packages

First, the module imports with import

cal.py:

# !/usr/bin/python def Add (x, y    ): return x+yif__name__'__main__':     Print Add (+)

Note: __name__ is a built-in variable and is a file name if the value is called __mail__ directly in the CLI.

Import in new.py:

Import Cal print cal.add (2,3);

II. Packages: Modules organized by directory name

1. Create a folder with the name of the package name

2. Create a __init__.py file under this folder

3. Store script files, compiled extensions, and sub-packages in this folder as needed

4, import in the file with import pack.m1,pack.m2,pack.m3

5, using Pack.m1.xxx to invoke the module in the package method

Sample directory Structure:

util/__init____init__. PYc

Call Example new.py:

Import util.cal print util.cal.add (2,3); 5

or using as to use aliases:

Import util.cal as C print c.add (2,3); 5

Or use the From to shorthand:

 from Import Add Print Add (2,3);

Python Learning note five: modules and packages