def find_difference(s, t):
 s_chars = Counter(s)
 t_chars = Counter(t)
 for c in t_chars:
  if (s_chars[c] < t_chars[c]):
   return c

def find_difference ( s , t ) : s_chars = Counter ( s ) t_chars = Counter ( t ) for c in t_chars : if ( s_chars [ c ] < t_chars [ c ] ) : return c
find the differing character between strings .