MAINT: Restore 3.6 functionality

ci/azure/azure_template_posix.yml

@@ -28,6 +28,8 @@ jobs:
           NUMPY: 1.16.6
         python39_latest:
           python.version: '3.9'
+        python36_latest:
+          python.version: '3.6'
         python38_mid_conda:
           python.version: '3.8'
           use.conda: true

randomgen/tests/test_recent_numpy_changes.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 from distutils.version import LooseVersion
 from typing import cast
 

randomgen/typing.py

@@ -1,13 +1,22 @@
-from typing import TYPE_CHECKING, Any, Optional, Sequence, Union
+import sys
+from typing import TYPE_CHECKING, Optional, Sequence, Union
 
-if TYPE_CHECKING:
-    from typing import Literal
+from randomgen.seed_sequence import SeedSequence
 
-    SeedMode = Literal["sequence", "legacy"]
+if sys.version_info >= (3, 8):
+    from typing import Literal
+elif TYPE_CHECKING:
+    from typing_extensions import Literal
 else:
-    SeedMode = Any
 
-from randomgen.seed_sequence import SeedSequence
+    class _Literal:
+        def __getitem__(self, item):
+            pass
+
+    Literal = _Literal()
+
+SeedMode = Literal["sequence", "legacy"]
+
 
 __all__ = ["IntegerSequenceSeed", "SeedMode", "Size"]
 

randomgen/xoshiro256starstar.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 from typing import Optional
 import warnings
 

randomgen/xoshiro512starstar.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 from typing import Optional
 import warnings
 

requirements-dev.txt

@@ -1,3 +1,4 @@
+black==21.4b1
 pytest>=6
 pytest-cov
 scipy>=1.3.2