code: def upgrade():
      """Apply Add processor_subdir to ImportError."""
      conn = op.get_bind()
  
      with op.batch_alter_table("import_error") as batch_op:
          if conn.dialect.name == "mysql":
              batch_op.add_column(
                  sa.Column(
                      "processor_subdir",
                      sa.Text(length=2000),
                      nullable=True,
                  )
              )
          else:
              batch_op.add_column(
                  sa.Column(
                      "processor_subdir",
                      sa.String(length=2000),
                      nullable=True,
                  )
              )
  
imports: import sqlalchemy
  from alembic import op
label_desc: Use image node_id 1 for calling a global function with example usage: upgrade() without return types