The node type in DeferredNode is just FuncItem.

Guido van Rossum · Guido van Rossum · commit 571f4251a6db · 2016-10-10T16:13:01.000-07:00
diff --git a/mypy/checker.py b/mypy/checker.py
@@ -64,7 +64,7 @@
 DeferredNode = NamedTuple(
     'DeferredNode',
     [
-        ('node', Union[Expression, Statement, FuncItem]),
+        ('node', FuncItem),
         ('context_type_name', Optional[str]),  # Name of the surrounding class (for error messages)
     ])
 

Original file line number	Diff line number	Diff line change
`@@ -64,7 +64,7 @@`
`64`	`64`	`DeferredNode = NamedTuple(`
`65`	`65`	`'DeferredNode',`
`66`	`66`	`[`
`67`		`- ('node', Union[Expression, Statement, FuncItem]),`
	`67`	`+ ('node', FuncItem),`
`68`	`68`	`('context_type_name', Optional[str]), # Name of the surrounding class (for error messages)`
`69`	`69`	`])`
`70`	`70`