def _check_prefix(self, lines, prefix, name, lineno):
for i, line in enumerate(lines):<EOL><INDENT>if line and not line.startswith(prefix):<EOL><INDENT>raise ValueError('<STR_LIT>'<EOL>'<STR_LIT>' %<EOL>(lineno+i+<NUM_LIT:1>, name, line))<EOL><DEDENT><DEDENT>
Check that every line in the given list starts with the given
prefix; if any line does not, then raise a ValueError.