compress.py

from itertools import compress

data = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]
selector = [1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1]

for i in compress(data, selector):
    print(i, end=" ")
# OUTPUT
# Simply prints all numbers for which the corresponding boolean value in selector
#is True, in this case all the even numbers upto 10.
"""
0 2 4 6 8 10
"""