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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_sparse(self):
 """ A sparse matrix representation of the faces. Returns sparse : scipy.sparse.coo_matrix Has properties: dtype : bool shape : (len(self.vertices), len(self.faces)) """

        sparse = geometry.index_sparse(
            column_count=len(self.vertices),
            indices=self.faces)
        return sparse