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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 get_subnet(self, subnet_id, **kwargs):
 """Returns information about a single subnet. :param string id: Either the ID for the subnet or its network identifier :returns: A dictionary of information about the subnet """

        if 'mask' not in kwargs:
            kwargs['mask'] = DEFAULT_SUBNET_MASK

        return self.subnet.getObject(id=subnet_id, **kwargs)