code: def test_dask_mg_pagerank(dask_client, directed):
      # Initialize and run pagerank on two distributed graphs
      # with same communicator
  
      input_data_path1 = (
          RAPIDS_DATASET_ROOT_DIR_PATH / "karate.csv"
      ).as_posix()
      print(f"dataset1={input_data_path1}")
      chunksize1 = dcg.get_chunksize(input_data_path1)
  
      input_data_path2 = (
          RAPIDS_DATASET_ROOT_DIR_PATH / "dolphins.csv"
      ).as_posix()
      print(f"dataset2={input_data_path2}")
      chunksize2 = dcg.get_chunksize(input_data_path2)
  
      ddf1 = dask_cudf.read_csv(
          input_data_path1,
          chunksize=chunksize1,
          delimiter=" ",
          names=["src", "dst", "value"],
          dtype=["int32", "int32", "float32"],
      )
  
      dg1 = cugraph.Graph(directed=directed)
      dg1.from_dask_cudf_edgelist(ddf1, "src", "dst")
  
      result_pr1 = dcg.pagerank(dg1).compute()
  
      ddf2 = dask_cudf.read_csv(
          input_data_path2,
          chunksize=chunksize2,
          delimiter=" ",
          names=["src", "dst", "value"],
          dtype=["int32", "int32", "float32"],
      )
  
      dg2 = cugraph.Graph(directed=directed)
      dg2.from_dask_cudf_edgelist(ddf2, "src", "dst")
  
      result_pr2 = dcg.pagerank(dg2).compute()
  
      # Calculate single GPU pagerank for verification of results
      df1 = cudf.read_csv(
          input_data_path1,
          delimiter=" ",
          names=["src", "dst", "value"],
          dtype=["int32", "int32", "float32"],
      )
  
      g1 = cugraph.Graph(directed=directed)
      g1.from_cudf_edgelist(df1, "src", "dst")
      expected_pr1 = cugraph.pagerank(g1)
  
      df2 = cudf.read_csv(
          input_data_path2,
          delimiter=" ",
          names=["src", "dst", "value"],
          dtype=["int32", "int32", "float32"],
      )
  
      g2 = cugraph.Graph(directed=directed)
      g2.from_cudf_edgelist(df2, "src", "dst")
      expected_pr2 = cugraph.pagerank(g2)
  
      # Compare and verify pagerank results
  
      err1 = 0
      err2 = 0
      tol = 1.0e-05
  
      compare_pr1 = expected_pr1.merge(
          result_pr1, on="vertex", suffixes=["_local", "_dask"]
      )
  
      assert len(expected_pr1) == len(result_pr1)
  
      for i in range(len(compare_pr1)):
          diff = abs(
              compare_pr1["pagerank_local"].iloc[i]
              - compare_pr1["pagerank_dask"].iloc[i]
          )
          if diff > tol * 1.1:
              err1 = err1 + 1
      print("Mismatches in ", input_data_path1, ": ", err1)
  
      assert len(expected_pr2) == len(result_pr2)
  
      compare_pr2 = expected_pr2.merge(
          result_pr2, on="vertex", suffixes=["_local", "_dask"]
      )
  
      for i in range(len(compare_pr2)):
          diff = abs(
              compare_pr2["pagerank_local"].iloc[i]
              - compare_pr2["pagerank_dask"].iloc[i]
          )
          if diff > tol * 1.1:
              err2 = err2 + 1
      print("Mismatches in ", input_data_path2, ": ", err2)
      assert err1 == err2 == 0
  
file_path: cugraph/python/cugraph/cugraph/tests/comms/test_comms_mg.py
imports: import gc
  import pytest
  import cugraph.dask
  import cudf
  import dask_cudf
  import cugraph
  from cugraph.testing.utils import RAPIDS_DATASET_ROOT_DIR_PATH
label_desc: Use image node_id 2 for calling a global function with example usage: test_dask_mg_pagerank(dask_client, directed) without return types