text: 
  """
  Tests for the PyPy cStringIO implementation.
  """
  
  class AppTestcStringIO:
      def setup_class(cls):
          cls.w_io = cls.space.appexec([], "(): import cStringIO; return cStringIO")
          cls.w_bytes = cls.space.wrap('some bytes')
  
  
      def test_reset(self):
          """
          Test that the reset method of cStringIO objects sets the position
          marker to the beginning of the stream.
          """
          io = self.io.StringIO()
          io.write(self.bytes)
          assert io.read() == ''
          io.reset()
          assert io.read() == self.bytes
  
          io = self.io.StringIO(self.bytes)
          assert io.read() == self.bytes
          assert io.read() == ''
          io.reset()
          assert io.read() == self.bytes
  