code: def test_cache(self):
      # GH 26565, GH26617, GH35432, GH53387
      # This test checks whether _cache has been set.
      # Calling RangeIndex._cache["_data"] creates an int64 array of the same length
      # as the RangeIndex and stores it in _cache.
      idx = RangeIndex(0, 100, 10)
  
      assert idx._cache == {}
  
      repr(idx)
      assert idx._cache == {}
  
      str(idx)
      assert idx._cache == {}
  
      idx.get_loc(20)
      assert idx._cache == {}
  
      90 in idx  # True
      assert idx._cache == {}
  
      91 in idx  # False
      assert idx._cache == {}
  
      idx.all()
      assert idx._cache == {}
  
      idx.any()
      assert idx._cache == {}
  
      for _ in idx:
          pass
      assert idx._cache == {}
  
      msg = "RangeIndex.format is deprecated"
      with tm.assert_produces_warning(FutureWarning, match=msg):
          idx.format()
      assert idx._cache == {}
  
      df = pd.DataFrame({"a": range(10)}, index=idx)
  
      # df.__repr__ should not populate index cache
      str(df)
      assert idx._cache == {}
  
      df.loc[50]
      assert idx._cache == {}
  
      with pytest.raises(KeyError, match="51"):
          df.loc[51]
      assert idx._cache == {}
  
      df.loc[10:50]
      assert idx._cache == {}
  
      df.iloc[5:10]
      assert idx._cache == {}
  
      # after calling take, _cache may contain other keys, but not "_data"
      idx.take([3, 0, 1])
      assert "_data" not in idx._cache
  
      df.loc[[50]]
      assert "_data" not in idx._cache
  
      df.iloc[[5, 6, 7, 8, 9]]
      assert "_data" not in idx._cache
  
      # idx._cache should contain a _data entry after call to idx._data
      idx._data
      assert isinstance(idx._data, np.ndarray)
      assert idx._data is idx._data  # check cached value is reused
      assert "_data" in idx._cache
      expected = np.arange(0, 100, 10, dtype="int64")
      tm.assert_numpy_array_equal(idx._cache["_data"], expected)
  
imports: import numpy
  import pytest
  from pandas.core.dtypes.common import ensure_platform_int
  import pandas
  from pandas import Index, RangeIndex
  import pandas._testing
label_desc: Use image node_id 20 for calling the TestRangeIndex obj's underlying member method code with example usage: obj.test_cache() without return types