Python - Intersectiing strings

Question

Trying to write a for function that takes two strings and returns the characters that intersect in the order that they appear in the first string.

Here\'s what I tri

Answer 1

def str_intersection(str1, str2):
    common_letters = set(str1) & set(str2)
    str3 = ''
    for c in str1:
        if (c in common_letters) and (c not in str3):
            str3 += c
    return str3