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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 default_depart(self, mdnode):
 """Default node depart handler If there is a matching ``visit_<type>`` method for a container node, then we should make sure to back up to it's parent element when the node is exited. """

        if mdnode.is_container():
            fn_name = 'visit_{0}'.format(mdnode.t)
            if not hasattr(self, fn_name):
                warn("Container node skipped: type={0}".format(mdnode.t))
            else:
                self.current_node = self.current_node.parent