code: def test_quantile_missing_group_values_correct_results(
      key, val, expected_key, expected_val
  ):
      # GH 28662, GH 33200, GH 33569
      df = DataFrame({"key": key, "val": val})
  
      expected = DataFrame(
          expected_val,
          index=Index(expected_key, name="key"),
          columns=["val"],
      )
  
      grp = df.groupby("key")
  
      result = grp.quantile(0.5)
      tm.assert_frame_equal(result, expected)
  
      result = grp.quantile()
      tm.assert_frame_equal(result, expected)
  
imports: import numpy
  import pytest
  import pandas
  from pandas import DataFrame, Index
  import pandas._testing
label_desc: Use image node_id 10 for calling a global function with example usage: test_quantile_missing_group_values_correct_results(key, val, expected_key, expected_val) without return types