Algorithm Interview: Shifted String

Hi, here's your problem today. This problem was recently asked by Apple:

You are given two strings, A and B. Return whether A can be shifted some number of times to get B.

Eg. A = abcde, B = cdeab should return true because A can be shifted 3 times to the right to get B. A = abc and B= acb should return false.

def is_shifted(a, b):

  # Fill this in.

  

print is_shifted('abcde', 'cdeab')

# True