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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 _value_iterator(self, task_name, param_name):
 """ Yield the parameter values, with optional deprecation warning as second tuple value. The parameter value will be whatever non-_no_value that is yielded first. """

        cp_parser = CmdlineParser.get_instance()
        if cp_parser:
            dest = self._parser_global_dest(param_name, task_name)
            found = getattr(cp_parser.known_args, dest, None)
            yield (self._parse_or_no_value(found), None)
        yield (self._get_value_from_config(task_name, param_name), None)
        if self._config_path:
            yield (self._get_value_from_config(self._config_path['section'], self._config_path['name']),
                   'The use of the configuration [{}] {} is deprecated. Please use [{}] {}'.format(
                       self._config_path['section'], self._config_path['name'], task_name, param_name))
        yield (self._default, None)