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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 prefix_del(self, prefix, route_dist=None):
 """ This method deletes a advertised prefix. ``prefix`` must be the string representation of an IP network. ``route_dist`` specifies a route distinguisher value. """

        func_name = 'network.del'
        networks = {
            PREFIX: prefix,
        }
        if route_dist:
            func_name = 'prefix.delete_local'
            networks[ROUTE_DISTINGUISHER] = route_dist

            rf, p = self._check_rf_and_normalize(prefix)
            networks[ROUTE_FAMILY] = rf
            networks[PREFIX] = p

        call(func_name, **networks)