code: def terminate_instance(
      self,
      instance_id: str,
      region: str,
      backend_data: Optional[str] = None,
  ):
      self.api_client.destroy_instance(instance_id)
  
imports: import time
  from typing import List, Optional
  import gpuhunt
  import requests
  from gpuhunt.providers.vastai import VastAIProvider
  from dstack._internal.core.backends.base import Compute
  from dstack._internal.core.backends.base.compute import get_docker_commands, get_instance_name
  from dstack._internal.core.backends.base.offers import get_catalog_offers
  from dstack._internal.core.backends.vastai.api_client import DISK_SIZE, VastAIAPIClient
  from dstack._internal.core.backends.vastai.config import VastAIConfig
  from dstack._internal.core.errors import ComputeError
  from dstack._internal.core.models.backends.base import BackendType
  from dstack._internal.core.models.instances import InstanceAvailability, InstanceOfferWithAvailability, LaunchedInstanceInfo
  from dstack._internal.core.models.runs import Job, Requirements, Run
  from dstack._internal.utils.logging import get_logger
label_desc: Use image node_id 4 for calling the VastAICompute obj's underlying member method code with example usage: obj.terminate_instance(instance_id, region, backend_data) without return types