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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 _tuplefy_namespace(self, namespace):
 """Converts a mongodb namespace to a db, collection tuple"""

        namespace_split = namespace.split('.', 1)
        if len(namespace_split) is 1:
            # we treat a single element as a collection name.
            # this also properly tuplefies '*'
            namespace_tuple = ('*', namespace_split[0])
        elif len(namespace_split) is 2:
            namespace_tuple = (namespace_split[0],namespace_split[1])
        else:
            return None
        return namespace_tuple