Lesson - 14 : Python3 - Python Flow Controls : for loop, while loop, do while

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Python Flow Controls : for loop, while loop, do while :
A loop statement allows us to execute a statement or group of statements multiple times. 
For loops can iterate over a sequence of numbers using the "range" and "xrange" functions.

while loop : Repeats a statement or group of statements while a given condition is TRUE. It tests the condition before executing the loop body.
for loop : Executes a sequence of statements multiple times and abbreviates the code that manages the loop variable.
nested loops : You can use one or more loop inside any another while, for or do..while loop.