diff --git a/synapse/config/jwt.py b/synapse/config/jwt.py
index 73b28473da16..49aaca7cf653 100644
--- a/synapse/config/jwt.py
+++ b/synapse/config/jwt.py
@@ -16,7 +16,7 @@
 
 from synapse.types import JsonDict
 
-from ._base import Config
+from ._base import Config, ConfigError
 
 MISSING_AUTHLIB = """Missing authlib library. This is required for jwt login.
 
@@ -45,7 +45,7 @@ def read_config(self, config: JsonDict, **kwargs: Any) -> None:
             try:
                 from authlib.jose import JsonWebToken
 
-                JsonWebToken # To stop unused lint.
+                JsonWebToken  # To stop unused lint.
             except ImportError:
                 raise ConfigError(MISSING_AUTHLIB)
         else: