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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 getDescriptor(self, desc_type, desc_index, length, endpoint = -1):
 r"""Retrieves a descriptor from the device identified by the type and index of the descriptor. Arguments: desc_type: descriptor type. desc_index: index of the descriptor. len: descriptor length. endpoint: ignored. """

        return control.get_descriptor(self.dev, length, desc_type, desc_index)