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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 get_sidecar_nodes(self) -> Iterator[PostSidecarNode]: """Sidecar nodes of a Post with typename==GraphSidecar."""

        if self.typename == 'GraphSidecar':
            for edge in self._field('edge_sidecar_to_children', 'edges'):
                node = edge['node']
                is_video = node['is_video']
                yield PostSidecarNode(is_video=is_video, display_url=node['display_url'],
                                      video_url=node['video_url'] if is_video else None)