pandas-dev
diff --git a/‎pandas/_typing.py
+1-1 b/‎pandas/_typing.py
+1-1
diff --git a/‎pandas/core/frame.py
+1 b/‎pandas/core/frame.py
+1
@@ -185,7 +185,7 @@
 ]
 
 # internals
-Manager = Union["ArrayManager", "BlockManager"]
+Manager = Union["ArrayManager", "BlockManager", "SingleBlockManager"]
 SingleManager = Union["SingleArrayManager", "SingleBlockManager"]
 
 # indexing
 
@@ -548,6 +548,7 @@ class DataFrame(NDFrame, OpsMixin):
     _HANDLED_TYPES = (Series, Index, ExtensionArray, np.ndarray)
     _accessors: set[str] = {"sparse"}
     _hidden_attrs: frozenset[str] = NDFrame._hidden_attrs | frozenset([])
+    _mgr: BlockManager | ArrayManager
 
     @property
     def _constructor(self) -> type[DataFrame]:
Original file line number	Diff line number	Diff line change
`@@ -185,7 +185,7 @@`
`185`	`185`	`]`
`186`	`186`
`187`	`187`	`# internals`
`188`		`-Manager = Union["ArrayManager", "BlockManager"]`
	`188`	`+Manager = Union["ArrayManager", "BlockManager", "SingleBlockManager"]`
`189`	`189`	`SingleManager = Union["SingleArrayManager", "SingleBlockManager"]`
`190`	`190`
`191`	`191`	`# indexing`