code: def test_rank_return_type_compatible_mode(method):
      # in compatible mode, rank() always returns floats
      pdf = pd.DataFrame({"a": [1, 1, 1, 2, 2], "b": [1, 2, 3, 4, 5]})
      with cudf.option_context("mode.pandas_compatible", True):
          df = cudf.from_pandas(pdf)
          result = df.groupby("a").rank(method=method)
      expect = pdf.groupby("a").rank(method=method)
      assert_eq(expect, result)
      assert result["b"].dtype == "float64"
  
imports: import pandas
  import pytest
  import cudf
  from cudf.testing._utils import assert_eq
label_desc: Use image node_id 1 for calling a global function with example usage: test_rank_return_type_compatible_mode(method) without return types