def get_lookup(self, operator):
        """Look up a lookup.

        :param operator: Name of the lookup operator
        """
        try:
            return self._lookups[operator]
        except KeyError:
            raise NotImplementedError("Lookup operator '{}' is not supported".format(operator))
def get_lookup ( self , operator ) : try : return self . _lookups [ operator ] except KeyError : raise NotImplementedError ( "Lookup operator '{}' is not supported" . format ( operator ) )
Look up a lookup.

        :param operator: Name of the lookup operator