class_docstr: This plan is used for pushing down query string directly to
  backend database engine.
code: def __hash__(self) -> int:
      return hash(
          (super().__hash__(), self._database_name, self._query_string)
      )
  
file_path: evadb/evadb/plan_nodes/native_plan.py
imports: from evadb.plan_nodes.abstract_plan import AbstractPlan
  from evadb.plan_nodes.types import PlanOprType
label_desc: Use image node_id 5 for calling the NativePlan obj's underlying member method code with example usage: obj.__hash__() and returns: hash