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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 validate_config(self, values, argv=None, strict=False):
 """Validate all config values through the command-line parser. This takes all supplied options (which could have been retrieved from a them by running them through argparser (and raises SystemExit on failure). :returns dict: key/values for all config values (from all sources) :raises: SystemExit """

        options = []
        for option in self._options:
            kwargs = option.kwargs.copy()
            if option.name in values:
                if 'default' in kwargs:
                    # Since we're overriding defaults, we need to
                    # preserve the default value for the help text:
                    help_text = kwargs.get('help')
                    if help_text:
                        if '(default: ' not in help_text:
                            kwargs['help'] = '%s (default: %s)' % (
                                help_text, kwargs['default']
                            )
                kwargs['default'] = values[option.name]
                kwargs['required'] = False  # since we have a value
            temp = Option(*option.args, **kwargs)
            options.append(temp)
        parser = self.build_parser(options,
                                   formatter_class=argparse.HelpFormatter)
        if argv:
            parsed, extras = parser.parse_known_args(argv[1:])
            if extras:
                valid, _ = self.parse_passthru_args(argv[1:])
                parsed, extras = parser.parse_known_args(valid)
                if extras and strict:  # still
                    self.build_parser(options)
                    parser.parse_args(argv[1:])
        else:
            parsed = parser.parse_args([])

        results = vars(parsed)
        raise_for_group = {}
        for option in self._options:
            if option.kwargs.get('required'):
                if option.dest not in results or results[option.dest] is None:
                    if getattr(option, '_mutexgroup', None):
                        raise_for_group.setdefault(option._mutexgroup, [])
                        raise_for_group[option._mutexgroup].append(
                            option._action)
                    else:
                        raise SystemExit("'%s' is required. See --help "
                                         "for more info." % option.name)
                else:
                    if getattr(option, '_mutexgroup', None):
                        raise_for_group.pop(option._mutexgroup, None)
        if raise_for_group:
            optstrings = [str(k.option_strings)
                          for k in raise_for_group.values()[0]]
            msg = "One of %s required. " % " ,".join(optstrings)
            raise SystemExit(msg + "See --help for more info.")
        return results