Ositus

def partition(part, s):
    if len(s) == 1:
        return 1
    else:
        part, s = part + s[0], s[1:]
        r = 0
        r += partition("", s)
        if s[0] not in part:
            r += partition(part, s)
        return r


s = input()

print(int(partition("", s) % (1_000_000_007)))

Test 1

Group: 1, 2, 3

Verdict: ACCEPTED

Test 2

Group: 1, 2, 3

Verdict: ACCEPTED

Test 3

Group: 1, 2, 3

Verdict: ACCEPTED

Test 4

Group: 1, 2, 3

Verdict: ACCEPTED

Test 5

Group: 2, 3

Verdict: TIME LIMIT EXCEEDED

Test 6

Group: 3

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    print(...

Test 7

Group: 3

Verdict: RUNTIME ERROR