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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 unmerge_vertices(self):
 """ Removes all face references so that every face contains three unique vertex indices and no faces are adjacent. """

        # new faces are incrementing so every vertex is unique
        faces = np.arange(len(self.faces) * 3,
                          dtype=np.int64).reshape((-1, 3))

        # use update_vertices to apply mask to
        # all properties that are per-vertex
        self.update_vertices(self.faces.reshape(-1))
        # set faces to incrementing indexes
        self.faces = faces
        # keep face normals as the haven't changed
        self._cache.clear(exclude=['face_normals'])