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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 faces_unique_edges(self):
 """ For each face return which indexes in mesh.unique_edges constructs that face. Returns --------- faces_unique_edges : (len(self.faces), 3) int Indexes of self.edges_unique that construct self.faces Examples --------- In [0]: mesh.faces[0:2] Out[0]: TrackedArray([[ 1, 6946, 24224], [ 6946, 1727, 24225]]) In [1]: mesh.edges_unique[mesh.faces_unique_edges[0:2]] Out[1]: array([[[ 1, 6946], [ 6946, 24224], [ 1, 24224]], [[ 1727, 6946], [ 1727, 24225], [ 6946, 24225]]]) """

        # make sure we have populated unique edges
        populate = self.edges_unique
        # we are relying on the fact that edges are stacked in triplets
        result = self._cache['edges_unique_inverse'].reshape((-1, 3))
        return result