Enumerate is a built-in function of Python. Its usefulness can not be summarized in a single line. Yet most of the newcomers and even some advanced programmers are unaware of it. It allows us to loop over something and have an automatic counter. Here is an example:
for counter, value in enumerate(some_list): print(counter, value)
And there is more!
enumerate also accepts an optional argument which
makes it even more useful.
my_list = ['apple', 'banana', 'grapes', 'pear'] for c, value in enumerate(my_list, 1): print(c, value) # Output: # 1 apple # 2 banana # 3 grapes # 4 pear
The optional argument allows us to tell
enumerate from where to
start the index. You can also create tuples containing the index and
list item using a list. Here is an example:
my_list = ['apple', 'banana', 'grapes', 'pear'] counter_list = list(enumerate(my_list, 1)) print(counter_list) # Output: [(1, 'apple'), (2, 'banana'), (3, 'grapes'), (4, 'pear')]