old_contents: import six
  from xcffib.ffi import ffi, bytes_to_cdata
  
  def test_bytes_to_cdata():
      bs = six.b('these are some bytes')
      assert bs == bytes(ffi.buffer(bytes_to_cdata(bs), len(bs)))
  
new_contents: import six
  from xcffib.ffi import ffi, bytes_to_cdata
  
  def test_bytes_to_cdata():
      bs = six.b('these are some bytes')
      assert bs == ffi.buffer(bytes_to_cdata(bs), len(bs))[:]
  
subject: Fix pypy by using alternate cffi minibuffer syntax