🐛 Fix typing & imports for python < 3.11

Author: MatteoBouvier

tests/test_annotated.py

@@ -1,4 +1,4 @@
-from enum import StrEnum, auto
+from enum import Enum
 
 import typer
 from typer.testing import CliRunner
@@ -84,9 +84,9 @@ class TestAnnotatedOptionAcceptsOptionalValue:
     def test_enum(self):
         app = typer.Typer()
 
-        class OptEnum(StrEnum):
-            val1 = auto()
-            val2 = auto()
+        class OptEnum(str, Enum):
+            val1 = "val1"
+            val2 = "val2"
 
         @app.command()
         def cmd(opt: Annotated[bool | OptEnum, typer.Option()] = OptEnum.val1):

typer/main.py

@@ -929,7 +929,7 @@ def get_click_param(
     else:
         annotation = str
     main_type = annotation
-    secondary_type: type[bool] | None = None
+    secondary_type: Union[Type[bool], None] = None
     is_list = False
     is_tuple = False
     parameter_type: Any = None