code: def downgrade():
      op.add_column(
          "dbs",
          sa.Column(
              "allow_run_sync",
              sa.Integer(display_width=1),
              autoincrement=False,
              nullable=True,
          ),
      )
  
imports: import sqlalchemy
  from alembic import op
label_desc: Use image node_id 2 for calling a global function with example usage: downgrade() without return types