code: def dynamic_label(self):
      return self.label + "!"
  
file_path: holoviews/holoviews/tests/core/test_operation.py
imports: import param
  from holoviews.core.operation import Operation
  from holoviews.element import Curve
  from holoviews.element.comparison import ComparisonTestCase
  from holoviews.streams import Params, Stream
label_desc: Use image node_id 1 for calling the ParamClass obj's underlying member method code with example usage: obj.dynamic_label() and returns: unknown