Shrink dict down to essentials

        :param shrink: Dict to shrink
        :type shrink: dict
        :return: Shrunk dict
        :rtype: dict

def _shrink_dict(self, shrink):
        """
        Shrink dict down to essentials

        :param shrink: Dict to shrink
        :type shrink: dict
        :return: Shrunk dict
        :rtype: dict
        """
        res = {}

        if len(shrink.keys()) == 1 and "value" in shrink:
            return self.shrink(shrink['value'])
        else:
            for a in shrink:
                res[a] = self.shrink(shrink[a])

                if not res[a]:
                    del res[a]
        return res