FIX: import Literal from typing_extensions

pyproject.toml

@@ -33,7 +33,7 @@ dependencies = [
     "particle",
     "python-constraint",
     "tqdm >=4.24.0", # autonotebook
-    'typing-extensions; python_version <"3.10.0"', # typing.TypeAlias
+    'typing-extensions; python_version <"3.10.0"', # Literal, Protocol, TypeAlias
 ]
 description = "Rule-based particle reaction problem solver on a quantum number level"
 dynamic = ["version"]

src/qrules/transition.py

@@ -10,7 +10,7 @@
 from copy import copy, deepcopy
 from enum import Enum, auto
 from multiprocessing import Pool
-from typing import TYPE_CHECKING, Iterable, Literal, Sequence, overload
+from typing import TYPE_CHECKING, Iterable, Sequence, overload
 
 import attrs
 from attrs import define, field, frozen
@@ -74,6 +74,11 @@
     create_n_body_topology,
 )
 
+if sys.version_info >= (3, 8):
+    from typing import Literal
+else:
+    from typing_extensions import Literal
+
 if sys.version_info >= (3, 10):
     from typing import TypeAlias
 else: