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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def ctrl_transfer(self, dev_handle, bmRequestType, bRequest, wValue, wIndex, data, timeout):
 r"""Perform a control transfer on the endpoint 0. The direction of the transfer is inferred from the bmRequestType field of the setup packet. dev_handle is the value returned by the open_device() method. bmRequestType, bRequest, wValue and wIndex are the same fields of the setup packet. data is an array object, for OUT requests it contains the bytes to transmit in the data stage and for IN requests it is the buffer to hold the data read. The number of bytes requested to transmit or receive is equal to the length of the array times the data.itemsize field. The timeout parameter specifies a time limit to the operation in miliseconds. Return the number of bytes written (for OUT transfers) or the data read (for IN transfers), as an array.array object. """

        _not_implemented(self.ctrl_transfer)