'Check if a header is in alphabetical order with the previous header.
Args:
clean_lines: A CleansedLines instance containing the file.
linenum: The number of the line to check.
header_path: Canonicalized header to be checked.
Returns:
Returns true if the header is in alphabetical order.'

def IsInAlphabeticalOrder(self, clean_lines, linenum, header_path):

    if ((self._last_header > header_path) and Match('^\\s*#\\s*include\\b', clean_lines.elided[(linenum - 1)])):
        return False
    return True
