diff --git a/fastapi/encoders.py b/fastapi/encoders.py
index 658eb3c61..d6b834141 100644
--- a/fastapi/encoders.py
+++ b/fastapi/encoders.py
@@ -64,9 +64,6 @@ ENCODERS_BY_TYPE: Dict[Type[Any], Callable[[Any], Any]] = {
     datetime.timedelta: lambda td: td.total_seconds(),
     Decimal: decimal_encoder,
     Enum: lambda o: o.value,
-    frozenset: list,
-    deque: list,
-    GeneratorType: list,
     IPv4Address: str,
     IPv4Interface: str,
     IPv4Network: str,
@@ -79,7 +76,6 @@ ENCODERS_BY_TYPE: Dict[Type[Any], Callable[[Any], Any]] = {
     Pattern: lambda o: o.pattern,
     SecretBytes: str,
     SecretStr: str,
-    set: list,
     UUID: str,
     UndefinedType: lambda _: None,
     Url: str,