code: def override_db(new_db: Database):
      global db
      db = new_db
  
file_path: dstack/src/dstack/_internal/server/db.py
imports: from contextlib import asynccontextmanager
  from alembic import command, config
  from sqlalchemy import event
  from sqlalchemy.engine.interfaces import DBAPIConnection
  from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine
  from sqlalchemy.orm import sessionmaker
  from sqlalchemy.pool import ConnectionPoolEntry
  from dstack._internal.server import settings
  from dstack._internal.server.settings import DATABASE_URL
label_desc: Use image node_id 1 for calling a global function with example usage: override_db(new_db) without return types