code: def test_check_integrity(self):
      locs = []
      lengths = []
  
      # 0-length OK
      BlockIndex(0, locs, lengths)
  
      # also OK even though empty
      BlockIndex(1, locs, lengths)
  
      msg = "Block 0 extends beyond end"
      with pytest.raises(ValueError, match=msg):
          BlockIndex(10, [5], [10])
  
      msg = "Block 0 overlaps"
      with pytest.raises(ValueError, match=msg):
          BlockIndex(10, [2, 5], [5, 3])
  
imports: import operator
  import numpy
  import pytest
  import pandas._libs.sparse
  import pandas.util._test_decorators
  from pandas import Series
  import pandas._testing
  from pandas.core.arrays.sparse import BlockIndex, IntIndex, make_sparse_index
label_desc: Use image node_id 4 for calling the TestBlockIndex obj's underlying member method code with example usage: obj.test_check_integrity() without return types