code: def downgrade():
      with op.batch_alter_table("table_columns") as batch_op:
          batch_op.alter_column(
              "type",
              existing_type=sa.TEXT(),
              type_=sa.VARCHAR(length=32),
          )
  
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