How to remove duplicates in an array in python

Question

I'm trying to implement a difference function, which subtracts one list from another and returns the result. Here is what i have so far:

def array_diff(a, b):
 for e in b[:]:
 for i in a:
 a.remove(i)
 return a
in1 = [1, 2, 2]
in2 = [1]
print(array_diff(in1, in2))

I have two sample tests that i'd like to run.

Test.assert_equals(array_diff([1,2,2], [1]), [2,2], "a was [1,2,2], b was [1], expected [2,2]")
Test.assert_equals(array_diff([1,2,2], [2]), [1], "a was [1,2,2], b was [2], expected [1]")

How would i be able to remove the same value more than once?

• Edeki Okoh: Does this answer your question? Delete intersection between two lists

Answer 1

array_diff = lambda a, b: [ i for i in a if i not in b]
array_diff(in1,[1])
 [2, 2]
array_diff(in1,[2])
 [1]