human
I wrote the below code

    import re
    change_re = re.compile('(\\++|\\-+|\\^+)')
    diff_lines_iterator = ndiff(fromlines, tolines, linejunk, charjunk)
    def _make_line(lines, format_key, side, num_lines=[0, 0]):
        'Returns    line    of    text    with    user\'s    change    markup    and    line    formatting.\n\n                                lines    --    list    of    lines    from    the    ndiff    generator    to    produce    a    line    of\n                                                                    text    from.        When    producing    the    line    of    text    to    return,    the\n                                                                    lines    used    are    removed    from    this    list.\n                                format_key    --    \'+\'    return    first    line    in    list    with    "add"    markup    around\n                                                                                                        the    entire    line.\n                                                                                        \'-\'    return    first    line    in    list    with    "delete"    markup    around\n                                                                                                        the    entire    line.\n                                                                                        \'?\'    return    first    line    in    list    with    add/delete/change\n                                                                                                        intraline    markup    (indices    obtained    from    second    line)\n                                                                                        None    return    first    line    in    list    with    no    markup\n                                side    --    indice    into    the    num_lines    list    (0=from,1=to)\n                                num_lines    --    from/to    current    line    number.        This    is    NOT    intended    to  ...

What's a good function header?

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Here's a good function header?
assistant
#Here's a good function header.

def _mdiff(fromlines, tolines, context=None, linejunk=None, charjunk=IS_CHARACTER_JUNK):