cek string version 2

cek_string2.py

from collections import Counter
def cek(string):
    if len(string) >= 2:
        return True if sum([1 for i in Counter(string).most_common() if i[1] >= 2]) >= 2 else False
    return False
    
print cek('aaabbcdeg')
print cek('aaaaaaaaab')
print cek('absjedeo')
print cek('aaaabbbbbccccdd')