code: def encode_body(self, f):
          
          num_bytes_written = 0
          num_bytes_written += self.__encode_name(f)
          num_bytes_written += self.__encode_protocol_level(f)
          num_bytes_written += self.__encode_connect_flags(f)
          num_bytes_written += self.__encode_keep_alive(f)
  
          num_bytes_written += mqtt_io.encode_utf8(self.client_id, f)
  
          if self.will is not None:
              num_bytes_written += mqtt_io.encode_utf8(self.will.topic, f)
              num_bytes_written += mqtt_io.encode_bytes(self.will.message, f)
  
          if self.username is not None:
              num_bytes_written += mqtt_io.encode_utf8(self.username, f)
  
          if self.password is not None:
              num_bytes_written += mqtt_io.encode_utf8(self.password, f)
  
          return num_bytes_written
docs: Parameters
          ----------
          f: file
              File-like object with a write method.
  
          Returns
          -------
          int
              Number of bytes written to ``f``.