@import url("chrome://global/skin/aboutReaderControls.css"); en.wikibooks.org A Beginner's Python Tutorial/Importing Modules 4-5 minutos @import url("chrome://global/skin/aboutReaderContent.css"); Introduction[edit]Last lesson we covered the killer topic of Classes. As you can remember, classes are neat combinations of variables and functions in a nice, neat package. Programming lingo calls this feature encapsulation, but regardless of what it is called, it's a really cool feature for keeping things together so the code can be used in many instances in lots of places. Of course, you've got to ask, "how do I get my classes to many places, in many programs?". The answer is to put them into a module, to be imported into other programs.Module? What's a Module?[edit]A module is a Python file that (generally) has only definitions of variables, functions, and classes. For example, a module might look like this:Code Example 1 - moduletest.py### EXAMPLE PYTHON MODULE# Define some variables:numberone = 1ageofqueen = 78# define some functionsdef printhello(): print "hello" def timesfour(input): print input * 4 # define a classclass Piano: def __init__(self): self.type = raw_input("What type of piano? ") self.height = raw_input("What height (in feet)? ") self.price = raw_input("How much did it cost? ") self.age = raw_input("How old is it (in years)? ") def printdetails(self): print "This piano is a/an " + self.height + " foot", print self.type, "piano, " + self.age, "years old and costing\ " + self.price + " dollars."As you see, a module looks pretty much like your normal Python program.So what do we do with a module? We import bits of it (or all of it) into other programs.To import all the variables, functions and classes from moduletest.py into another program you are writing, we use the import operator. For example, to import moduletest.py into your main program, you would have this:Code Example 2 - mainprogram.py### mainprogam.py### IMPORTS ANOTHER MODULEimport moduletestThis assumes that the module is in the same directory as mainprogram.py, or is a default module that comes with python. You leave out the '.py' at the end of the file - it is ignored. You normally put all import statements at the beginning of the python file, but technically they can be anywhere. In order to use the items of the module in your main program, you use the following:Code Example 3 - mainprogram.py continued### USING AN IMPORTED MODULE# Use the form modulename.itemname# Examples:print moduletest.ageofqueencfcpiano = moduletest.Piano()cfcpiano.printdetails()As you see, the modules that you import act very much like the classes we looked at last lesson - anything inside them must be preceeded with modulename for it to work.More About Module[edit]Wish you could get rid of the modulename. part that you have to put before every item you use from a module? No? Never? Well, I'll teach it to you anyway.One way to avoid this hassle is to import only the wanted objects from the module. To do this, you use the from operator. You use it in the form of from modulename import itemname. Here is an example:Code Example 4 - importing individual objects### IMPORT ITEMS DIRECTLY INTO YOUR PROGRAM# import themfrom moduletest import ageofqueenfrom moduletest import printhello# now try using themprint ageofqueenprinthello()What