how to use filter() in python code example

Example: what are filters in python

In simple words, the filter() method filters the given iterable 
with the help of a function that tests
each element in the iterable to be true or not.

Filter Methods is simply a like comprarator class of c++ STL


Code Explanation: 
  # A simple tutorial to show the filter 
# methods in python

grades = ['A','B','C','F']

def remove_fails(grades):
    return grades!='F'

print(list(filter(remove_fails,grades)))