code: def worker_type(self) -> str:
      return self._worker_type
  
file_path: hail/batch/batch/cloud/gcp/instance_config.py
imports: from typing import List, Union
  from ...driver.billing_manager import ProductVersions
  from ...instance_config import InstanceConfig
  from .resource_utils import gcp_machine_type_to_parts, machine_family_to_gpu
  from .resources import GCPAcceleratorResource, GCPComputeResource, GCPDynamicSizedDiskResource, GCPIPFeeResource, GCPLocalSSDStaticSizedDiskResource, GCPMemoryResource, GCPResource, GCPServiceFeeResource, GCPStaticSizedDiskResource, GCPSupportLogsSpecsAndFirewallFees, gcp_resource_from_dict
label_desc: Use image node_id 3 for calling the GCPSlimInstanceConfig obj's underlying member method code with example usage: obj.worker_type() and returns: self