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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 unregister(self, uuid):
 """Unregister a schema registered with input uuid. :raises: KeyError if uuid is not already registered. """

        schema = self._schbyuuid.pop(uuid)

        # clean schemas by name
        self._schbyname[schema.name].remove(schema)
        if not self._schbyname[schema.name]:
            del self._schbyname[schema.name]