code: def test_merge():
      # Repro Issue#3366
      with dask_cuda.LocalCUDACluster(n_workers=1) as cluster:
          with Client(cluster):
              r1 = cudf.DataFrame()
              r1["a1"] = range(4)
              r1["a2"] = range(4, 8)
              r1["a3"] = range(4)
  
              r2 = cudf.DataFrame()
              r2["b0"] = range(4)
              r2["b1"] = range(4)
              r2["b1"] = r2.b1.astype("str")
  
              d1 = dask_cudf.from_cudf(r1, 2)
              d2 = dask_cudf.from_cudf(r2, 2)
  
              res = d1.merge(d2, left_on=["a3"], right_on=["b0"])
              assert len(res) == 4
  
file_path: cudf/python/dask_cudf/dask_cudf/tests/test_distributed.py
imports: import numba.cuda
  import pytest
  import dask
  from dask import dataframe
  from dask.distributed import Client
  from distributed.utils_test import cleanup, loop, loop_in_thread
  import cudf
  from cudf.testing._utils import assert_eq
  import dask_cudf
label_desc: Use image node_id 3 for calling a global function with example usage: test_merge() without return types