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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 set_faces(self, faces):
 """Set the faces Parameters faces : ndarray (Nf, 3) array of faces. Each row in the array contains three indices into the vertex array, specifying the three corners of a triangular face. """

        self._faces = faces
        self._edges = None
        self._edges_indexed_by_faces = None
        self._vertex_faces = None
        self._vertices_indexed_by_faces = None
        self.reset_normals()
        self._vertex_colors_indexed_by_faces = None
        self._face_colors_indexed_by_faces = None