code: def upgrade():
      """Create Index."""
      op.create_index(
          "idx_xcom_dag_task_date",
          "xcom",
          ["dag_id", "task_id", "execution_date"],
          unique=False,
      )
  
imports: from __future__ import annotations
  from alembic import op
label_desc: Use image node_id 1 for calling a global function with example usage: upgrade() without return types