def METHOD_NAME(s):
  checksum = 0
  for i, c in enumerate(s[1:]):
    if c == "*":
      if i != len(s) - 4: # should be 3rd to last character
        print("ERROR: NMEA string does not have checksum delimiter in correct location:", s)
        return False
      break
    checksum ^= ord(c)
  else:
    print("ERROR: NMEA string does not have checksum delimiter:", s)
    return False
  return True