human
Complete this python program:
def abs(table, field):
assistant
#Here is the Python code you requested.

    """For a given <fieldname>, returns the absolute <tablename>.<fieldname>.
    This is useful when constructing queries with relations to other tables.
    """
    def _format(s):
        if (not ('.' in s)):
            p = ((s.endswith(')') and re.match((('^(' + sql_functions) + ')\\('), s, re.I)) or None)
            i = ((p and len(p.group(0))) or 0)
            return ('%s%s.%s' % (s[:i], table, s[i:]))
        return s
    if isinstance(field, (list, tuple)):
        return [_format(f) for f in field]
    return _format(field)