def lopen_loc(x):
    """Extracts the line and column number for a node that may have an opening
    parenthesis, brace, or bracket.
    """
    lineno = x._lopen_lineno if hasattr(x, "_lopen_lineno") else x.lineno
    col = x._lopen_col if hasattr(x, "_lopen_col") else x.col_offset
    return lineno, col