Fix SymbolicReference reference typing

2 files changed, 5 insertions, 3 deletions

diff --git a/git/refs/head.py b/git/refs/head.py
index 338efce9..4b9bf33c 100644
--- a/git/refs/head.py
+++ b/git/refs/head.py
@@ -142,7 +142,7 @@ class Head(Reference):
             flag = "-D"
         repo.git.branch(flag, *heads)
 
-    def set_tracking_branch(self, remote_reference: 'RemoteReference') -> 'Head':
+    def set_tracking_branch(self, remote_reference: Union['RemoteReference', None]) -> 'Head':
         """
         Configure this branch to track the given remote reference. This will alter
             this branch's configuration accordingly.
diff --git a/git/refs/symbolic.py b/git/refs/symbolic.py
index 0e9dad5c..9a5a4479 100644
--- a/git/refs/symbolic.py
+++ b/git/refs/symbolic.py
@@ -28,6 +28,7 @@ from git.types import Commit_ish, PathLike, TBD, Literal
 
 if TYPE_CHECKING:
     from git.repo import Repo
+    from git.refs import Reference
 
 T_References = TypeVar('T_References', bound='SymbolicReference')
 
@@ -356,8 +357,9 @@ class SymbolicReference(object):
         return self
 
     # aliased reference
-    reference = property(_get_reference, set_reference, doc="Returns the Reference we point to")
-    ref: Union[Commit_ish] = reference     # type: ignore  # Union[str, Commit_ish, SymbolicReference]
+    reference: Union[Commit_ish, 'Reference'] = property(                 # type: ignore
+        _get_reference, set_reference, doc="Returns the Reference we point to")
+    ref = reference
 
     def is_valid(self):
         """