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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 remove_namespace(self, ns_uri):
 """Removes the indicated namespace from this set."""

        if not self.contains_namespace(ns_uri):
            return

        ni = self.__ns_uri_map.pop(ns_uri)
        for prefix in ni.prefixes:
            del self.__prefix_map[prefix]