how to keep elements of a list based on another list

Question

I have two lists looking like:

list1 = [\'a\',\'a\',\'b\',\'b\',\'b\',\'c\',\'d\',\'e\',\'e\',\'g\',\'g\']

list2 = [\'a\',\'c\',\'z\',\'y\']

Answer 1

One alternative approach with numpy:

import numpy as np

np.asarray(list1)[np.in1d(list1, list2)].tolist()
#['a', 'a', 'c']