@pimms.require<EOL><INDENT>def validate_tess(tess, coordinates):<DEDENT>
(d,n) = coordinates.shape<EOL>if tess.vertex_count != n:<EOL><INDENT>raise ValueError('<STR_LIT>')<EOL><DEDENT>if d != <NUM_LIT:2> and d != <NUM_LIT:3>:<EOL><INDENT>raise ValueError('<STR_LIT>')<EOL><DEDENT>return True<EOL>
mesh.validate_tess requires that all faces be valid indices into mesh.coordinates.