code: def setControl(
              self, request_type, request, value, index, buffer_or_len,
              callback=None, user_data=None, timeout=0):
          
          if self.__submitted:
              raise ValueError('Cannot alter a submitted transfer')
          if self.__doomed:
              raise DoomedTransferError('Cannot reuse a doomed transfer')
          if isinstance(buffer_or_len, (int, long)):
              length = buffer_or_len
              # pylint: disable=undefined-variable
              string_buffer, transfer_py_buffer = create_binary_buffer(
                  length + CONTROL_SETUP_SIZE,
              )
              # pylint: enable=undefined-variable
          else:
              length = len(buffer_or_len)
              string_buffer, transfer_py_buffer = create_binary_buffer(
                  CONTROL_SETUP + buffer_or_len,
              )
          self.__initialized = False
          self.__transfer_buffer = string_buffer
          # pylint: disable=undefined-variable
          self.__transfer_py_buffer = integer_memoryview(
              transfer_py_buffer,
          )[CONTROL_SETUP_SIZE:]
          # pylint: enable=undefined-variable
          self.__user_data = user_data
          libusb1.libusb_fill_control_setup(
              string_buffer, request_type, request, value, index, length)
          libusb1.libusb_fill_control_transfer(
              self.__transfer, self.__handle, string_buffer,
              self.__ctypesCallbackWrapper, None, timeout)
          self.__callback = callback
          self.__initialized = True
docs: Setup transfer for control use.
  
          request_type, request, value, index
              See USBDeviceHandle.controlWrite.
              request_type defines transfer direction (see
              ENDPOINT_OUT and ENDPOINT_IN)).
          buffer_or_len
              Either a string (when sending data), or expected data length (when
              receiving data).
          callback
              Callback function to be invoked on transfer completion.
              Called with transfer as parameter, return value ignored.
          user_data
              User data to pass to callback function.
          timeout
              Transfer timeout in milliseconds. 0 to disable.