def represent_dict(self, data):
        # type: (Any) -> Any
        """write out tag if saved on loading"""
        try:
            t = data.tag.value
        except AttributeError:
            t = None
        if t:
            if t.startswith('!!'):
                tag = 'tag:yaml.org,2002:' + t[2:]
            else:
                tag = t
        else:
            tag = u'tag:yaml.org,2002:map'
        return self.represent_mapping(tag, data)
write out tag if saved on loading
dynaconf/vendor/ruamel/yaml/representer.py