code: def worker_type_and_cores(self, machine_type: str) -> Tuple[str, int]:
      return gcp_machine_type_to_worker_type_and_cores(machine_type)
  
imports: import logging
  import uuid
  from typing import List, Tuple
  import aiohttp
  from hailtop.aiocloud import aiogoogle
  from hailtop.utils.time import parse_timestamp_msecs
  from ....driver.instance import Instance
  from ....driver.resource_manager import CloudResourceManager, UnknownVMState, VMDoesNotExist, VMState, VMStateCreating, VMStateRunning, VMStateTerminated
  from ....file_store import FileStore
  from ....instance_config import InstanceConfig, QuantifiedResource
  from ..instance_config import GCPSlimInstanceConfig
  from ..resource_utils import GCP_MACHINE_FAMILY, family_worker_type_cores_to_gcp_machine_type, gcp_machine_type_to_worker_type_and_cores, gcp_worker_memory_per_core_mib
  from .billing_manager import GCPBillingManager
  from .create_instance import create_vm_config
label_desc: Use image node_id 3 for calling the GCPResourceManager obj's underlying member method code with example usage: obj.worker_type_and_cores(machine_type) and returns: gcp_machine_type_to_worker_type_and_cores