Refactors type hints for clarity

Updates type hints in `crud.py`, `helpers.py`, and `models.py` for improved readability and maintainability.

Replaces `Merchant | None` with `Optional[Merchant]` and `list[X]` with `List[X]` for consistency with standard Python typing practices.

crud.py

@@ -1,4 +1,5 @@
 import json
+from typing import List, Optional, Tuple
 
 from lnbits.helpers import urlsafe_short_hash
 
@@ -43,7 +44,7 @@ async def create_merchant(user_id: str, m: PartialMerchant) -> Merchant:
 
 async def update_merchant(
     user_id: str, merchant_id: str, config: MerchantConfig
-) -> Merchant | None:
+) -> Optional[Merchant]:
     await db.execute(
         f"""
             UPDATE nostrmarket.merchants SET meta = :meta, time = {db.timestamp_now}
@@ -54,7 +55,7 @@ async def update_merchant(
     return await get_merchant(user_id, merchant_id)
 
 
-async def touch_merchant(user_id: str, merchant_id: str) -> Merchant | None:
+async def touch_merchant(user_id: str, merchant_id: str) -> Optional[Merchant]:
     await db.execute(
         f"""
             UPDATE nostrmarket.merchants SET time = {db.timestamp_now}
@@ -65,7 +66,7 @@ async def touch_merchant(user_id: str, merchant_id: str) -> Merchant | None:
     return await get_merchant(user_id, merchant_id)
 
 
-async def get_merchant(user_id: str, merchant_id: str) -> Merchant | None:
+async def get_merchant(user_id: str, merchant_id: str) -> Optional[Merchant]:
     row: dict = await db.fetchone(
         """SELECT * FROM nostrmarket.merchants WHERE user_id = :user_id AND id = :id""",
         {
@@ -77,7 +78,7 @@ async def get_merchant(user_id: str, merchant_id: str) -> Merchant | None:
     return Merchant.from_row(row) if row else None
 
 
-async def get_merchant_by_pubkey(public_key: str) -> Merchant | None:
+async def get_merchant_by_pubkey(public_key: str) -> Optional[Merchant]:
     row: dict = await db.fetchone(
         """SELECT * FROM nostrmarket.merchants WHERE public_key = :public_key""",
         {"public_key": public_key},
@@ -86,7 +87,7 @@ async def get_merchant_by_pubkey(public_key: str) -> Merchant | None:
     return Merchant.from_row(row) if row else None
 
 
-async def get_merchants_ids_with_pubkeys() -> list[tuple[str, str]]:
+async def get_merchants_ids_with_pubkeys() -> List[Tuple[str, str]]:
     rows: list[dict] = await db.fetchall(
         """SELECT id, public_key FROM nostrmarket.merchants""",
     )
@@ -94,7 +95,7 @@ async def get_merchants_ids_with_pubkeys() -> list[tuple[str, str]]:
     return [(row["id"], row["public_key"]) for row in rows]
 
 
-async def get_merchant_for_user(user_id: str) -> Merchant | None:
+async def get_merchant_for_user(user_id: str) -> Optional[Merchant]:
     row: dict = await db.fetchone(
         """SELECT * FROM nostrmarket.merchants WHERE user_id = :user_id """,
         {"user_id": user_id},
@@ -137,7 +138,7 @@ async def create_zone(merchant_id: str, data: Zone) -> Zone:
     return zone
 
 
-async def update_zone(merchant_id: str, z: Zone) -> Zone | None:
+async def update_zone(merchant_id: str, z: Zone) -> Optional[Zone]:
     await db.execute(
         """
         UPDATE nostrmarket.zones
@@ -156,7 +157,7 @@ async def update_zone(merchant_id: str, z: Zone) -> Zone | None:
     return await get_zone(merchant_id, z.id)
 
 
-async def get_zone(merchant_id: str, zone_id: str) -> Zone | None:
+async def get_zone(merchant_id: str, zone_id: str) -> Optional[Zone]:
     row: dict = await db.fetchone(
         "SELECT * FROM nostrmarket.zones WHERE merchant_id = :merchant_id AND id = :id",
         {
@@ -167,7 +168,7 @@ async def get_zone(merchant_id: str, zone_id: str) -> Zone | None:
     return Zone.from_row(row) if row else None
 
 
-async def get_zones(merchant_id: str) -> list[Zone]:
+async def get_zones(merchant_id: str) -> List[Zone]:
     rows: list[dict] = await db.fetchall(
         "SELECT * FROM nostrmarket.zones WHERE merchant_id = :merchant_id",
         {"merchant_id": merchant_id},
@@ -234,7 +235,7 @@ async def create_stall(merchant_id: str, data: Stall) -> Stall:
     return stall
 
 
-async def get_stall(merchant_id: str, stall_id: str) -> Stall | None:
+async def get_stall(merchant_id: str, stall_id: str) -> Optional[Stall]:
     row: dict = await db.fetchone(
         """
         SELECT * FROM nostrmarket.stalls
@@ -248,7 +249,7 @@ async def get_stall(merchant_id: str, stall_id: str) -> Stall | None:
     return Stall.from_row(row) if row else None
 
 
-async def get_stalls(merchant_id: str, pending: bool | None = False) -> list[Stall]:
+async def get_stalls(merchant_id: str, pending: Optional[bool] = False) -> List[Stall]:
     rows: list[dict] = await db.fetchall(
         """
         SELECT * FROM nostrmarket.stalls
@@ -273,7 +274,7 @@ async def get_last_stall_update_time() -> int:
     return row["event_created_at"] or 0 if row else 0
 
 
-async def update_stall(merchant_id: str, stall: Stall) -> Stall | None:
+async def update_stall(merchant_id: str, stall: Stall) -> Optional[Stall]:
     await db.execute(
         """
             UPDATE nostrmarket.stalls
@@ -397,7 +398,9 @@ async def update_product(merchant_id: str, product: Product) -> Product:
     return updated_product
 
 
-async def update_product_quantity(product_id: str, new_quantity: int) -> Product | None:
+async def update_product_quantity(
+    product_id: str, new_quantity: int
+) -> Optional[Product]:
     await db.execute(
         """
             UPDATE nostrmarket.products SET quantity = :quantity
@@ -412,7 +415,7 @@ async def update_product_quantity(product_id: str, new_quantity: int) -> Product
     return Product.from_row(row) if row else None
 
 
-async def get_product(merchant_id: str, product_id: str) -> Product | None:
+async def get_product(merchant_id: str, product_id: str) -> Optional[Product]:
     row: dict = await db.fetchone(
         """
             SELECT * FROM nostrmarket.products
@@ -428,8 +431,8 @@ async def get_product(merchant_id: str, product_id: str) -> Product | None:
 
 
 async def get_products(
-    merchant_id: str, stall_id: str, pending: bool | None = False
-) -> list[Product]:
+    merchant_id: str, stall_id: str, pending: Optional[bool] = False
+) -> List[Product]:
     rows: list[dict] = await db.fetchall(
         """
         SELECT * FROM nostrmarket.products
@@ -442,8 +445,8 @@ async def get_products(
 
 
 async def get_products_by_ids(
-    merchant_id: str, product_ids: list[str]
-) -> list[Product]:
+    merchant_id: str, product_ids: List[str]
+) -> List[Product]:
     # todo: revisit
 
     keys = []
@@ -464,7 +467,7 @@ async def get_products_by_ids(
     return [Product.from_row(row) for row in rows]
 
 
-async def get_wallet_for_product(product_id: str) -> str | None:
+async def get_wallet_for_product(product_id: str) -> Optional[str]:
     row: dict = await db.fetchone(
         """
         SELECT s.wallet as wallet FROM nostrmarket.products p
@@ -571,7 +574,7 @@ async def create_order(merchant_id: str, o: Order) -> Order:
     return order
 
 
-async def get_order(merchant_id: str, order_id: str) -> Order | None:
+async def get_order(merchant_id: str, order_id: str) -> Optional[Order]:
     row: dict = await db.fetchone(
         """
             SELECT * FROM nostrmarket.orders
@@ -585,7 +588,7 @@ async def get_order(merchant_id: str, order_id: str) -> Order | None:
     return Order.from_row(row) if row else None
 
 
-async def get_order_by_event_id(merchant_id: str, event_id: str) -> Order | None:
+async def get_order_by_event_id(merchant_id: str, event_id: str) -> Optional[Order]:
     row: dict = await db.fetchone(
         """
             SELECT * FROM nostrmarket.orders
@@ -599,7 +602,7 @@ async def get_order_by_event_id(merchant_id: str, event_id: str) -> Order | None
     return Order.from_row(row) if row else None
 
 
-async def get_orders(merchant_id: str, **kwargs) -> list[Order]:
+async def get_orders(merchant_id: str, **kwargs) -> List[Order]:
     q = " AND ".join(
         [
             f"{field[0]} = :{field[0]}"
@@ -626,7 +629,7 @@ async def get_orders(merchant_id: str, **kwargs) -> list[Order]:
 
 async def get_orders_for_stall(
     merchant_id: str, stall_id: str, **kwargs
-) -> list[Order]:
+) -> List[Order]:
     q = " AND ".join(
         [
             f"{field[0]} = :{field[0]}"
@@ -651,7 +654,7 @@ async def get_orders_for_stall(
     return [Order.from_row(row) for row in rows]
 
 
-async def update_order(merchant_id: str, order_id: str, **kwargs) -> Order | None:
+async def update_order(merchant_id: str, order_id: str, **kwargs) -> Optional[Order]:
     q = ", ".join(
         [
             f"{field[0]} = :{field[0]}"
@@ -675,7 +678,7 @@ async def update_order(merchant_id: str, order_id: str, **kwargs) -> Order | Non
     return await get_order(merchant_id, order_id)
 
 
-async def update_order_paid_status(order_id: str, paid: bool) -> Order | None:
+async def update_order_paid_status(order_id: str, paid: bool) -> Optional[Order]:
     await db.execute(
         "UPDATE nostrmarket.orders SET paid = :paid  WHERE id = :id",
         {"paid": paid, "id": order_id},
@@ -689,7 +692,7 @@ async def update_order_paid_status(order_id: str, paid: bool) -> Order | None:
 
 async def update_order_shipped_status(
     merchant_id: str, order_id: str, shipped: bool
-) -> Order | None:
+) -> Optional[Order]:
     await db.execute(
         """
             UPDATE nostrmarket.orders
@@ -753,7 +756,7 @@ async def create_direct_message(
     return msg
 
 
-async def get_direct_message(merchant_id: str, dm_id: str) -> DirectMessage | None:
+async def get_direct_message(merchant_id: str, dm_id: str) -> Optional[DirectMessage]:
     row: dict = await db.fetchone(
         """
             SELECT * FROM nostrmarket.direct_messages
@@ -769,7 +772,7 @@ async def get_direct_message(merchant_id: str, dm_id: str) -> DirectMessage | No
 
 async def get_direct_message_by_event_id(
     merchant_id: str, event_id: str
-) -> DirectMessage | None:
+) -> Optional[DirectMessage]:
     row: dict = await db.fetchone(
         """
         SELECT * FROM nostrmarket.direct_messages
@@ -783,7 +786,7 @@ async def get_direct_message_by_event_id(
     return DirectMessage.from_row(row) if row else None
 
 
-async def get_direct_messages(merchant_id: str, public_key: str) -> list[DirectMessage]:
+async def get_direct_messages(merchant_id: str, public_key: str) -> List[DirectMessage]:
     rows: list[dict] = await db.fetchall(
         """
         SELECT * FROM nostrmarket.direct_messages
@@ -795,7 +798,7 @@ async def get_direct_messages(merchant_id: str, public_key: str) -> list[DirectM
     return [DirectMessage.from_row(row) for row in rows]
 
 
-async def get_orders_from_direct_messages(merchant_id: str) -> list[DirectMessage]:
+async def get_orders_from_direct_messages(merchant_id: str) -> List[DirectMessage]:
     rows: list[dict] = await db.fetchall(
         """
         SELECT * FROM nostrmarket.direct_messages
@@ -856,7 +859,7 @@ async def create_customer(merchant_id: str, data: Customer) -> Customer:
     return customer
 
 
-async def get_customer(merchant_id: str, public_key: str) -> Customer | None:
+async def get_customer(merchant_id: str, public_key: str) -> Optional[Customer]:
     row: dict = await db.fetchone(
         """
             SELECT * FROM nostrmarket.customers
@@ -870,7 +873,7 @@ async def get_customer(merchant_id: str, public_key: str) -> Customer | None:
     return Customer.from_row(row) if row else None
 
 
-async def get_customers(merchant_id: str) -> list[Customer]:
+async def get_customers(merchant_id: str) -> List[Customer]:
     rows: list[dict] = await db.fetchall(
         "SELECT * FROM nostrmarket.customers WHERE merchant_id = :merchant_id",
         {"merchant_id": merchant_id},
@@ -878,7 +881,7 @@ async def get_customers(merchant_id: str) -> list[Customer]:
     return [Customer.from_row(row) for row in rows]
 
 
-async def get_all_unique_customers() -> list[Customer]:
+async def get_all_unique_customers() -> List[Customer]:
     q = """
             SELECT public_key, MAX(merchant_id) as merchant_id, MAX(event_created_at)
             FROM nostrmarket.customers