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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 outline(self, face_ids=None, **kwargs):
 """ Given a list of face indexes find the outline of those faces and return it as a Path3D. The outline is defined here as every edge which is only included by a single triangle. Note that this implies a non-watertight mesh as the outline of a watertight mesh is an empty path. Parameters face_ids : (n,) int Indices to compute the outline of. If None, outline of full mesh will be computed. **kwargs: passed to Path3D constructor Returns path : Path3D Curve in 3D of the outline """

        from .path.exchange.misc import faces_to_path
        from .path.exchange.load import _create_path

        path = _create_path(**faces_to_path(self,
                                            face_ids,
                                            **kwargs))
        return path