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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _do_create_keywords(args, kw):
 """This converts any arguments after the action argument into their equivalent keywords and adds them to the kw argument. """

    v = kw.get('varlist', ())
    # prevent varlist="FOO" from being interpreted as ['F', 'O', 'O']
    if is_String(v): v = (v,)
    kw['varlist'] = tuple(v)
    if args:
        # turn positional args into equivalent keywords
        cmdstrfunc = args[0]
        if cmdstrfunc is None or is_String(cmdstrfunc):
            kw['cmdstr'] = cmdstrfunc
        elif callable(cmdstrfunc):
            kw['strfunction'] = cmdstrfunc
        else:
            raise SCons.Errors.UserError(
                'Invalid command display variable type. '
                'You must either pass a string or a callback which '
                'accepts (target, source, env) as parameters.')
        if len(args) > 1:
            kw['varlist'] = tuple(SCons.Util.flatten(args[1:])) + kw['varlist']
    if kw.get('strfunction', _null) is not _null \
                      and kw.get('cmdstr', _null) is not _null:
        raise SCons.Errors.UserError(
            'Cannot have both strfunction and cmdstr args to Action()')