code: def test_difference(c=BitSet):
      assert c([1, 3, 50, 72]) - c([3, 72]) == c([1, 50])
      assert list(c([1, 3, 50, 72]).difference([3, 72])) == [1, 50]
      b = c([1, 3, 50, 72])
      b.difference_update(c([3, 72]))
      assert list(b) == [1, 50]
      b = c([1, 3, 50, 72])
      b.difference_update([3, 72])
      assert list(b) == [1, 50]
  
file_path: whoosh/tests/test_bits.py
imports: from whoosh.filedb.filestore import RamStorage
  from whoosh.idsets import BitSet, OnDiskBitSet, SortedIntSet
label_desc: Use image node_id 5 for calling a global function with example usage: test_difference(c) without return types