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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 include(self, node):
 """Include the defined yaml file."""

        result = None
        if isinstance(node, ScalarNode):
            result = Loader.include_file(self.construct_scalar(node))
        else:
            raise RuntimeError("Not supported !include on type %s" % type(node))
        return result