Fix: api/models> ignore unfixable error [python/mypy #4284]

If 'base class is returned from a function', mypy won't treat it
propery.
This is reported and commented by collaborator as *Unsupported feature*
python/mypy#4284

Author: Cj-bc

api/models.py

@@ -7,7 +7,7 @@
 db = SQLAlchemy()
 
 
-class User(db.Model):
+class User(db.Model): # type: ignore
     """
         User model for DB
         Args:
@@ -34,7 +34,7 @@ def __repr__(self) -> str:
                f'{self.win_count}-{self.lose_count}>'
 
 
-class Classroom(db.Model):
+class Classroom(db.Model): # type: ignore
     """
         Classroom model for DB
         Args:
@@ -64,7 +64,7 @@ def get_classroom_name(self) -> str:
         return names[self.index]
 
 
-class Lottery(db.Model):
+class Lottery(db.Model): # type: ignore
     """
         Lottery model for DB
         Args:
@@ -90,7 +90,7 @@ def __repr__(self) -> str:
         return "<Lottery {}.{}>".format(self.classroom, self.index)
 
 
-class Application(db.Model):
+class Application(db.Model): # type: ignore
     """application model for DB
         DB contents:
             id (int): application unique id
@@ -163,7 +163,7 @@ def set_status(self, newstatus: str) -> None:
         db.session.commit()
 
 
-class GroupMember(db.Model):
+class GroupMember(db.Model): # type: ignore
     """group-member model for DB
         DB contents:
             id (int): group member unique id
@@ -193,7 +193,7 @@ def __repr__(self) -> str:
         return f"<GroupMember {self.user}>"
 
 
-class Error(db.Model):
+class Error(db.Model): # type: ignore
     """
         Error model
         DB contents: