diff --git a/app.py b/app.py
index c0ad3e0..5c731c2 100644
--- a/app.py
+++ b/app.py
@@ -155,6 +155,7 @@ class Receipt(db.Model):
     filesize = db.Column(db.Integer, nullable=True)
     file_hash = db.Column(db.String(64), nullable=True, unique=True)
 
+
 with app.app_context():
     db.create_all()
     from werkzeug.security import generate_password_hash
@@ -256,11 +257,12 @@ def enrich_list_data(l):
     l.total_expense = sum(e.amount for e in expenses)
     return l
 
+
 def save_resized_image(file, path):
     try:
         image = Image.open(file)
-        image.verify()            # sprawdzenie poprawności pliku
-        file.seek(0)              # reset do początku
+        image.verify()  # sprawdzenie poprawności pliku
+        file.seek(0)  # reset do początku
         image = Image.open(file)  # ponowne otwarcie po verify()
     except Exception:
         raise ValueError("Nieprawidłowy plik graficzny")
@@ -989,7 +991,10 @@ def upload_receipt(list_id):
         db.session.add(new_receipt)
         db.session.commit()
 
-        if request.is_json or request.headers.get("X-Requested-With") == "XMLHttpRequest":
+        if (
+            request.is_json
+            or request.headers.get("X-Requested-With") == "XMLHttpRequest"
+        ):
             url = url_for("uploaded_file", filename=webp_filename)
             socketio.emit("receipt_added", {"url": url}, to=str(list_id))
             return jsonify({"success": True, "url": url})
@@ -1000,7 +1005,6 @@ def upload_receipt(list_id):
     return _receipt_error("Niedozwolony format pliku")
 
 
-
 @app.route("/uploads/<filename>")
 def uploaded_file(filename):
     response = send_from_directory(app.config["UPLOAD_FOLDER"], filename)
@@ -1264,6 +1268,7 @@ def rotate_receipt(receipt_id):
 
     return redirect(request.referrer or url_for("admin_receipts", id="all"))
 
+
 @app.route("/admin/rename_receipt/<int:receipt_id>")
 @login_required
 @admin_required
@@ -1317,6 +1322,7 @@ def delete_receipt(receipt_id):
 
     return redirect(request.referrer or url_for("admin_receipts", id="all"))
 
+
 @app.route("/admin/generate_receipt_hash/<int:receipt_id>")
 @login_required
 @admin_required
@@ -1332,6 +1338,7 @@ def generate_receipt_hash(receipt_id):
         return redirect(request.referrer)
 
     import hashlib
+
     try:
         with open(file_path, "rb") as f:
             file_hash = hashlib.sha256(f.read()).hexdigest()