Loop over an ordered sequence, such as a list, and print each item as follows:

>>> food = ['ham', 'egg', 'spam']
>>> for snack in food:
...     print(snack)
...
ham
egg
spam

And remember that, as always, indentation matters in Python. We loop over a range of values with the built-in range() or xrange() functions. The latter function is slightly more efficient in certain cases. Loop over the numbers 1-9 with a step of 2 as follows:

>>> for i in range(1, 9, 2):
...     print(i)
...
1
3
5
7

The start and step parameter of the range() function are optional with default values of 1. We can also prematurely end a loop. Loop over the numbers 0-9 and break out of the loop when you reach 3:

>>> for i in range(9):
...     print(i)
...     if i == 3:
...     print('Three')
...     break
...
0
1
2
3
Three

The loop stopped at 3 and we did not print the higher numbers. Instead of leaving the loop, we can also get out of the current iteration. Print the numbers 0-4, skipping 3 as follows:

>>> for i in range(5):
...     if i == 3:
...             print('Three')
...             continue
...     print(i)
...
0
1
2
Three
4

The last line in the loop was not executed when we reached 3 because of the continue statement. In Python, the for loop can have an else statement attached to it. Add an else clause as follows:

>>> for i in range(5):
...     print(i)
... else:
...     print(i, 'in else clause')
...
0
1
2
3
4
(4, 'in else clause')

Python executes the code in the else clause last. Python also has a while loop. I do not use it that much because the for loop is more useful in my opinion.