Returns a mapping of {resource_id: {tagkey: tagvalue}}

def get_resource_tag_map(self, r_type, ids):
        """
        Returns a mapping of {resource_id: {tagkey: tagvalue}}
        """
        manager = self.manager.get_resource_manager(r_type)
        r_id = manager.resource_type.id
        # TODO only fetch resource with the given ids.
        return {
            r[r_id]: {t['Key']: t['Value'] for t in r.get('Tags', [])}
            for r in manager.resources() if r[r_id] in ids
        }