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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 del_ns(self, namespace):
 """ will remove a namespace ref from the manager. either Arg is optional. args: namespace: prefix, string or Namespace() to remove """

        # remove the item from the namespace dict
        namespace = str(namespace)
        attr_name = None
        if hasattr(self, namespace):
            delattr(self, namespace)