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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 _convert_dict_to_list_tuples(self, headers_dict):
 # type: (Dict[str, str]) -> List[Tuple[str, str]] """Convert headers dict to list of string tuples format for `ApiClientResponse` headers variable. :param headers_dict: Dictionary of headers in keys as strings and values as comma separated strings :type headers_dict: Dict[str, str] :return: List of tuples made up of two element strings from headers of client response :rtype: List[Tuple[str, str]] """

        headers_list = []
        if headers_dict is not None:
            for key, values in six.iteritems(headers_dict):
                for value in values.split(","):
                    value = value.strip()
                    if value is not None and value is not '':
                        headers_list.append((key, value.strip()))
        return headers_list