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COMPUTER SOFTWARE APPLICATION - CITS

Looping Through an Iterator
We can also use a for loop to iterate through an iterable object:
Create an Iterator
To create an object/class as an iterator you have to implement the methods __iter__() and __next__() to your
object.
As you have learned in the Python Classes/Objects chapter, all classes have a function called __init__(), which
allows you to do some initializing when the object is being created.

The __iter__() method acts similar, you can do operations (initializing etc.), but must always return the iterator
object itself.
The __next__() method also allows you to do operations, and must return the next item in the sequence.

Example
Create an iterator that returns numbers, starting with 1, and each sequence will increase by one (returning
1,2,3,4,5 etc.):

class MyNumbers:
def __iter__(self):
self.a = 1
return self

def __next__(self):
x = self.a
self.a += 1

return x
myclass = MyNumbers()
myiter = iter(myclass)

print(next(myiter))
print(next(myiter))
print(next(myiter))

print(next(myiter))
print(next(myiter))

Python Modules

Create a Module
To create a module just save the code you want in a file with the file extension .py:
Python Modules
In this tutorial, we will explain how to construct and import custom Python modules. Additionally, we may import
or integrate Python’s built-in modules via various methods.
What is Modular Programming?
Modular programming is the practice of segmenting a single, complicated coding task into multiple, simpler,
easier-to-manage sub-tasks. We call these subtasks modules. Therefore, we can build a bigger program by
assembling different modules that act like building blocks.
Modularizing our code in a big application has a lot of benefits.

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CITS : IT&ITES - Computer Software Application - Lesson 120 - 137 CITS : IT&ITES - Computer Software Application - Lesson 120 - 137