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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 _tuple_requested(self, namespace_tuple):
 """Helper for _namespace_requested. Supports limited wildcards"""

        if not isinstance(namespace_tuple[0], unicode):
            encoded_db = unicode(namespace_tuple[0])
        else:
            encoded_db = namespace_tuple[0]
        if not isinstance(namespace_tuple[1], unicode):
            encoded_coll = unicode(namespace_tuple[1])
        else:
            encoded_coll = namespace_tuple[1]

        if namespace_tuple is None:
            return False
        elif len(self._requested_namespaces) is 0:
            return True
        for requested_namespace in self._requested_namespaces:
            if  ((((requested_namespace[0]) == u'*') or
                 (encoded_db == requested_namespace[0])) and
                (((requested_namespace[1]) == u'*') or
                 (encoded_coll == requested_namespace[1]))):
                return True
        return False