code: def dask_client():
      # start_dask_client will check for the SCHEDULER_FILE and
      # DASK_WORKER_DEVICES env vars and use them when creating a client if
      # set. start_dask_client will also initialize the Comms singleton.
      dask_client, dask_cluster = start_dask_client(
          worker_class=IncreasedCloseTimeoutNanny
      )
  
      yield dask_client
  
      stop_dask_client(dask_client, dask_cluster)
  
imports: import pytest
  from cugraph.testing.mg_utils import start_dask_client, stop_dask_client
  import os
  import tempfile
  from dask_cuda.utils_test import IncreasedCloseTimeoutNanny
label_desc: Use image node_id 1 for calling a global function with example usage: dask_client() without return types