code: def upgrade():
      with op.batch_alter_table("params") as batch_op:
          batch_op.alter_column(
              "value",
              existing_type=sa.String(500),
              # We choose 8000 because it's the minimum max_length for
              # a VARCHAR column in all supported database types.
              type_=sa.String(8000),
              existing_nullable=False,
              existing_server_default=None,
          )
  
imports: from alembic import op
  import sqlalchemy
label_desc: Use image node_id 1 for calling a global function with example usage: upgrade() without return types