def trailing_blank_lines(physical_line, lines, line_number):
    """
    JCR: Trailing blank lines are superfluous.

    >>> trailing_blank_lines('\\n', ['SELECT 1','\\n'], 2)
    (0, 'W391 blank line at end of file')
    """
    if physical_line.strip() == '' and line_number == len(lines):
        return 0, 'W391 blank line at end of file'
