code: def write(self, fptr):
          
          length = 4 + 4 + 16 + len(self.raw_data)
          write_buffer = struct.pack('>I4s', length, b'uuid')
          fptr.write(write_buffer)
          fptr.write(self.uuid.bytes)
          fptr.write(self.raw_data)
docs: Write a UUID box to file.