Simplify datatime fields (remove sa_type=DateTime(timezone=True))

Author: YuriiMotov

backend/app/models.py

@@ -2,7 +2,6 @@
 from datetime import UTC, datetime
 
 from pydantic import EmailStr
-from sqlalchemy import DateTime
 from sqlmodel import Field, Relationship, SQLModel
 
 
@@ -52,10 +51,7 @@ class UpdatePassword(SQLModel):
 class User(UserBase, table=True):
     id: uuid.UUID = Field(default_factory=uuid.uuid4, primary_key=True)
     hashed_password: str
-    created_at: datetime | None = Field(
-        default_factory=get_datetime_utc,
-        sa_type=DateTime(timezone=True),  # type: ignore
-    )
+    created_at: datetime | None = Field(default_factory=get_datetime_utc)
     items: list[Item] = Relationship(back_populates="owner", cascade_delete=True)
 
 
@@ -90,10 +86,7 @@ class ItemUpdate(SQLModel):
 # Database model, database table inferred from class name
 class Item(ItemBase, table=True):
     id: uuid.UUID = Field(default_factory=uuid.uuid4, primary_key=True)
-    created_at: datetime | None = Field(
-        default_factory=get_datetime_utc,
-        sa_type=DateTime(timezone=True),  # type: ignore
-    )
+    created_at: datetime | None = Field(default_factory=get_datetime_utc)
     owner_id: uuid.UUID = Field(
         foreign_key="user.id", nullable=False, ondelete="CASCADE"
     )