diff --git a/src/pretix/base/services/pricing.py b/src/pretix/base/services/pricing.py
index af5dddfac..2c71f7db8 100644
--- a/src/pretix/base/services/pricing.py
+++ b/src/pretix/base/services/pricing.py
@@ -21,7 +21,7 @@
 #
 import re
 from decimal import Decimal
-from typing import List, Optional, Tuple
+from typing import List, Optional, Tuple, Union
 
 from django import forms
 from django.db.models import Q
@@ -156,7 +156,7 @@ def get_line_price(price_after_voucher: Decimal, custom_price_input: Decimal, cu
     return price
 
 
-def apply_discounts(event: Event, sales_channel: str | SalesChannel,
+def apply_discounts(event: Event, sales_channel: Union[str, SalesChannel],
                     positions: List[Tuple[int, Optional[int], Decimal, bool, bool, Decimal]],
                     collect_potential_discounts=None) -> List[Tuple[Decimal, Optional[Discount]]]:
     """