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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 register_module(self, module, namespace=None):
 """ Register a module. :param module: must be a string or a module object to register. :type module: str :param namespace: Namespace tag. If it is None module will be used as namespace tag :type namespace: str """

        namespace = namespace if namespace is not None else module \
            if isinstance(module, str) else module.__name__
        self.register_namespace(namespace, module)