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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 _add_namespace(self, namespace):
 """Add an included and possibly renamed Namespace."""

        src_name = namespace.source_name
        if "*" in src_name:
            self._regex_map.append((namespace_to_regex(src_name), namespace))
        else:
            self._add_plain_namespace(namespace)