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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 clean_protocol(self, protocol):
 """ A lot of measurement types make use of a protocol value, so we handle that here. """

        if protocol is not None:
            try:
                return self.PROTOCOL_MAP[protocol]
            except KeyError:
                self._handle_malformation(
                    '"{protocol}" is not a recognised protocol'.format(
                        protocol=protocol
                    )
                )