code: def test_nth_empty():
      # GH 16064
      df = DataFrame(index=[0], columns=["a", "b", "c"])
      result = df.groupby("a").nth(10)
      expected = df.iloc[:0]
      tm.assert_frame_equal(result, expected)
  
      result = df.groupby(["a", "b"]).nth(10)
      expected = df.iloc[:0]
      tm.assert_frame_equal(result, expected)
  
imports: import numpy
  import pytest
  import pandas
  from pandas import DataFrame, Index, MultiIndex, Series, Timestamp, isna
  import pandas._testing
label_desc: Use image node_id 24 for calling a global function with example usage: test_nth_empty() without return types