def assert_gro_equal(path, ref_path):
diff_out = StringIO()<EOL>with open(path) as stream, open(ref_path) as ref_stream:<EOL><INDENT>differences = compare_gro(stream, ref_stream)<EOL>format_gro_diff(differences, outstream=diff_out)<EOL>assert len(differences) == <NUM_LIT:0>, '<STR_LIT:\n>' + diff_out.getvalue()<EOL><DEDENT>
Raise an AssertionError if two GRO files are not semantically identical.