docs: def _derive_db(self):
          """
          this may not have a client on __init__, so this is deferred to
          a @property descriptor
          """
          client = self
          while hasattr(client, 'proxied'):
              client = client.proxied
          if hasattr(client, 'client'):
              client = client.client
              self._connection_kwargs = client.connection_pool.connection_kwargs
              self._db = self._connection_kwargs['db']
          else:
              self._connection_kwargs = False
              self._db = 'n/a'