code: def worker_type(self) -> str:
      return self._worker_type
  
file_path: hail/batch/batch/cloud/azure/instance_config.py
imports: from typing import List
  from hailtop.utils import filter_none
  from ...driver.billing_manager import ProductVersions
  from ...instance_config import InstanceConfig
  from .resource_utils import azure_machine_type_to_worker_type_and_cores
  from .resources import AzureDynamicSizedDiskResource, AzureIPFeeResource, AzureResource, AzureServiceFeeResource, AzureStaticSizedDiskResource, AzureVMResource, azure_resource_from_dict
label_desc: Use image node_id 3 for calling the AzureSlimInstanceConfig obj's underlying member method code with example usage: obj.worker_type() and returns: self