fix: use valid trove classifier and clean up unused imports

https://chatgpt.com/share/69468609-0584-800f-a3e0-9d58210fb0e8

tests/test_migration.py

@@ -1,7 +1,5 @@
 from __future__ import annotations
 
-import importlib.util
-import os
 import sys
 import tempfile
 import textwrap
@@ -16,7 +14,8 @@ class TestMigration(unittest.TestCase):
         with tempfile.TemporaryDirectory() as td:
             root = Path(td)
             mod = root / "roles_list.py"
-            mod.write_text(textwrap.dedent("""\
+            mod.write_text(
+                textwrap.dedent("""\
             __all__ = ["add", "PUBLIC_CONST"]
             PUBLIC_CONST = 123
             _PRIVATE_CONST = 999
@@ -29,7 +28,8 @@ class TestMigration(unittest.TestCase):
 
             if __name__ == "__main__":
                 print("running as script")
-            """),encoding="utf-8",
+            """),
+                encoding="utf-8",
             )
 
             migrate_one(mod, use_git=False, repo_root=root)
@@ -61,7 +61,8 @@ class TestMigration(unittest.TestCase):
         with tempfile.TemporaryDirectory() as td:
             root = Path(td)
             mod = root / "foo.py"
-            mod.write_text(textwrap.dedent("""\
+            mod.write_text(
+                textwrap.dedent("""\
             VALUE = "ok"
 
             def hello() -> str:
@@ -69,7 +70,9 @@ class TestMigration(unittest.TestCase):
 
             def _private() -> str:
                 return "no"
-            """), encoding="utf-8")
+            """),
+                encoding="utf-8",
+            )
             migrate_one(mod, use_git=False, repo_root=root)
 
             sys.path.insert(0, str(root))