Re-insert if isinstance(node, ast.Constant): into py _parse_annotation

As master drop python 3.5 support, conditional

    if sys.version_info >= (3, 6):

not needed anymore.  This hunk had got lost in merge.

	modified:   sphinx/domains/python.py

1 files changed, 6 insertions, 0 deletions

diff --git a/sphinx/domains/python.py b/sphinx/domains/python.py
index 80028e2b2..02a32f47c 100644
--- a/sphinx/domains/python.py
+++ b/sphinx/domains/python.py
@@ -143,6 +143,12 @@ def _parse_annotation(annotation: str, env: BuildEnvironment = None) -> List[Nod
 
             return result
         else:
+            if isinstance(node, ast.Constant):  # type: ignore
+                if node.value is Ellipsis:
+                    return [addnodes.desc_sig_punctuation('', "...")]
+                else:
+                    return [nodes.Text(node.value)]
+
             if sys.version_info < (3, 8):
                 if isinstance(node, ast.Ellipsis):
                     return [addnodes.desc_sig_punctuation('', "...")]