A for loop

In Python, a for loop is used to execute a task for n times. A for loop iterates through each element of a sequence. This sequence could be a dictionary, list, or any other iterator. For example, let's discuss an example where we execute a loop:

    for i in range(0, 10): 
       print("Loop execution no: ", i)

In the preceding example, the print statement is executed 10 times:

In order to execute the print task 10 times, the range() function (https://docs.python.org/2/library/functions.html#range) was used. The range function generates a list of numbers for a start and stop values that are passed as an arguments to the function. In this case, 0 and 10 are passed as arguments to the range() function. This returns a list containing numbers from 0 to 9. The for loop iterates through the code block for each element in steps of 1. The range function can also generate a list of numbers in steps of 2. This is done by passing the start value, stop value, and the step value as arguments to the range() function:

    for i in range(0, 20, 2): 
       print("Loop execution no: ", i)

In this example, 0 is the start value, 20 is the stop value, and 2 is the step value. This generates a list of 10 numbers in steps of two:

The range function can be used to count down from a given number. Let's say we would like to count down from 10 to 1:

    for i in range(10, 0, -1): 
       print("Count down no: ", i)

The output would be something like:

The general syntax of the range function is range(start, stop, step_count). It generates a sequence of numbers from start to n-1 where n is the stop value.