diff --git a/aerich/utils.py b/aerich/utils.py
index 14664a0..6e4fb88 100644
--- a/aerich/utils.py
+++ b/aerich/utils.py
@@ -4,7 +4,7 @@ import re
 import sys
 from pathlib import Path
 from types import ModuleType
-from typing import Dict, Optional
+from typing import Dict, Optional, Union
 
 from click import BadOptionUsage, ClickException, Context
 from tortoise import BaseDBAsyncClient, Tortoise
@@ -95,7 +95,7 @@ def is_default_function(string: str) -> Optional[re.Match]:
     return re.match(r"^<function.+>$", str(string or ""))
 
 
-def import_py_file(file: Path) -> ModuleType:
+def import_py_file(file: Union[str, Path]) -> ModuleType:
     module_name, file_ext = os.path.splitext(os.path.split(file)[-1])
     spec = importlib.util.spec_from_file_location(module_name, file)
     module = importlib.util.module_from_spec(spec)  # type:ignore[arg-type]
diff --git a/tests/test_utils.py b/tests/test_utils.py
index 654bc0d..9d640d2 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -1,6 +1,6 @@
 from aerich.utils import import_py_file
 
 
-def test_import_py_file():
+def test_import_py_file() -> None:
     m = import_py_file("aerich/utils.py")
     assert getattr(m, "import_py_file")