input: def is_joyful(s):
      """Given a string s, determine if it is joyful.
      A string is considered joyful if its length is at least 3 and every trio of consecutive characters are unique.
      Examples:
      is_joyful(a) => False
      is_joyful(aa) => False
      is_joyful(abcd) => True
      is_joyful(aabb) => False
      is_joyful(adb) => True
      is_joyful(xyy) => False
      """
output:     
      if len(s) < 3:
          return False
      for i in range(len(s) - 2):
          if s[i] == s[i + 1] or s[i] == s[i + 2] or s[i + 1] == s[i + 2]:
              return False
      return True
  