diff --git a/stdlib/2/__builtin__.pyi b/stdlib/2/__builtin__.pyi
index 5c552dec2..6b1d17874 100644
--- a/stdlib/2/__builtin__.pyi
+++ b/stdlib/2/__builtin__.pyi
@@ -43,6 +43,7 @@ class object:
     def __format__(self, format_spec: str) -> str: ...
     def __getattribute__(self, name: str) -> Any: ...
     def __delattr__(self, name: str) -> None: ...
+    def __sizeof__(self) -> int: ...
 
 class type(object):
     __bases__ = ...  # type: Tuple[type, ...]
diff --git a/stdlib/2/sqlite3/dbapi2.pyi b/stdlib/2/sqlite3/dbapi2.pyi
index 7a6dcf18e..bd4443323 100644
--- a/stdlib/2/sqlite3/dbapi2.pyi
+++ b/stdlib/2/sqlite3/dbapi2.pyi
@@ -79,12 +79,12 @@ def register_adapter(type: type, callable: Any) -> None: ...
 # TODO: sqlite3.register_converter.__doc__ specifies callable as unknown
 def register_converter(typename: str, callable: bytes) -> None: ...
 
-class Cache:
+class Cache(object):
     def __init__(self, *args, **kwargs) -> None: ...
     def display(self, *args, **kwargs) -> None: ...
     def get(self, *args, **kwargs) -> None: ...
 
-class Connection:
+class Connection(object):
     DataError = ...  # type: Any
     DatabaseError = ...  # type: Any
     Error = ...  # type: Any
@@ -165,7 +165,7 @@ class NotSupportedError(DatabaseError): ...
 
 class OperationalError(DatabaseError): ...
 
-class OptimizedUnicode:
+class OptimizedUnicode(object):
     maketrans = ...  # type: Any
     def __init__(self, *args, **kwargs): ...
     def capitalize(self, *args, **kwargs): ...
@@ -229,14 +229,13 @@ class OptimizedUnicode:
     def __ne__(self, other): ...
     def __rmod__(self, other): ...
     def __rmul__(self, other): ...
-    def __sizeof__(self): ...
 
-class PrepareProtocol:
+class PrepareProtocol(object):
     def __init__(self, *args, **kwargs): ...
 
 class ProgrammingError(DatabaseError): ...
 
-class Row:
+class Row(object):
     def __init__(self, *args, **kwargs): ...
     def keys(self, *args, **kwargs): ...
     def __eq__(self, other): ...
@@ -250,7 +249,7 @@ class Row:
     def __lt__(self, other): ...
     def __ne__(self, other): ...
 
-class Statement:
+class Statement(object):
     def __init__(self, *args, **kwargs): ...
 
 class Warning(Exception): ...
diff --git a/stdlib/3/builtins.pyi b/stdlib/3/builtins.pyi
index 742b932f6..7811b228c 100644
--- a/stdlib/3/builtins.pyi
+++ b/stdlib/3/builtins.pyi
@@ -46,6 +46,7 @@ class object:
     def __format__(self, format_spec: str) -> str: ...
     def __getattribute__(self, name: str) -> Any: ...
     def __delattr__(self, name: str) -> None: ...
+    def __sizeof__(self) -> int: ...
 
     if sys.version_info >= (3, 6):
         def __init_subclass__(cls) -> None: ...
diff --git a/stdlib/3/decimal.pyi b/stdlib/3/decimal.pyi
index 5106e465d..e77328854 100644
--- a/stdlib/3/decimal.pyi
+++ b/stdlib/3/decimal.pyi
@@ -224,7 +224,6 @@ class Decimal(SupportsInt, SupportsFloat, SupportsAbs[Decimal], SupportsRound[in
     def __rpow__(self, other: int) -> Decimal: ...
     def __rsub__(self, other: int) -> Decimal: ...
     def __rtruediv__(self, other: int) -> Decimal: ...
-    def __sizeof__(self) -> int: ...
     def __sub__(self, other: _Decimal) -> Decimal: ...
     def __truediv__(self, other: _Decimal) -> Decimal: ...
     def __trunc__(self) -> int: ...
diff --git a/stdlib/3/sqlite3/dbapi2.pyi b/stdlib/3/sqlite3/dbapi2.pyi
index dcc202687..ef46085cb 100644
--- a/stdlib/3/sqlite3/dbapi2.pyi
+++ b/stdlib/3/sqlite3/dbapi2.pyi
@@ -229,7 +229,6 @@ class OptimizedUnicode:
     def __ne__(self, other): ...
     def __rmod__(self, other): ...
     def __rmul__(self, other): ...
-    def __sizeof__(self): ...
 
 class PrepareProtocol:
     def __init__(self, *args, **kwargs): ...