code: def test_decode(self):
      msg = {"content": {"data": "Test"}}
      decoded = JupyterComm.decode(msg)
      self.assertEqual(decoded, "Test")
  
file_path: holoviews/holoviews/tests/plotting/test_comms.py
imports: from pyviz_comms import Comm, JupyterComm
  from holoviews.element.comparison import ComparisonTestCase
label_desc: Use image node_id 3 for calling the TestJupyterComm obj's underlying member method code with example usage: obj.test_decode() without return types