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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 face_angles_sparse(mesh):
 """ A sparse matrix representation of the face angles. Returns sparse: scipy.sparse.coo_matrix with: dtype: float shape: (len(mesh.vertices), len(mesh.faces)) """

    matrix = coo_matrix((mesh.face_angles.flatten(),
                         (mesh.faces_sparse.row, mesh.faces_sparse.col)),
                        mesh.faces_sparse.shape)
    return matrix