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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 find_all(self, node_type):
 """Find all the nodes of a given type. If the type is a tuple, the check is performed for any of the tuple items. """

        for child in self.iter_child_nodes():
            if isinstance(child, node_type):
                yield child
            for result in child.find_all(node_type):
                yield result