Probable fix for #535 - use union instead of | operator for python 3.9 compatibility

lcsc_api.py

@@ -2,6 +2,7 @@
 
 import io
 from pathlib import Path
+from typing import Union
 
 import requests  # pylint: disable=import-error
 
@@ -31,7 +32,7 @@ def get_part_data(self, lcsc_number: str) -> dict:
             }
         return {"success": True, "data": data}
 
-    def download_bitmap(self, url: str) -> io.BytesIO | None:
+    def download_bitmap(self, url: str) -> Union[io.BytesIO, None]:
         """Download a picture of the part from the API."""
         content = requests.get(url, headers=self.headers, timeout=10).content
         return io.BytesIO(content)

store.py

@@ -6,6 +6,7 @@
 import os
 from pathlib import Path
 import sqlite3
+from typing import Union
 
 from .helpers import (
     dict_factory,
@@ -131,7 +132,7 @@ def get_part(self, ref: str) -> dict:
                 {"reference": ref},
             ).fetchone()
 
-    def set_stock(self, ref: str, stock: int | None):
+    def set_stock(self, ref: str, stock: Union[int, None]):
         """Set the stock value for a part in the database."""
         with contextlib.closing(sqlite3.connect(self.dbfile)) as con, con as cur:
             cur.execute(