code: def get_javascript(cls, stream=None):
      if stream is None:
          output = io.StringIO()
      else:
          output = stream
      super(FigureManagerNbAgg, cls).get_javascript(stream=output)
      with io.open(
          os.path.join(
              os.path.dirname(__file__),
              "web_backend",
              "js",
              "nbagg_mpl.js",
          ),
          encoding="utf8",
      ) as fd:
          output.write(fd.read())
      if stream is None:
          return output.getvalue()
  
imports: import six
  from base64 import b64encode
  import io
  import json
  import os
  import uuid
  from IPython.display import display, Javascript, HTML
  from matplotlib import rcParams, is_interactive
  from matplotlib._pylab_helpers import Gcf
  from matplotlib.backend_bases import _Backend, FigureCanvasBase, NavigationToolbar2
  from matplotlib.backends.backend_webagg_core import FigureCanvasWebAggCore, FigureManagerWebAgg, NavigationToolbar2WebAgg, TimerTornado
label_desc: Use image node_id 6 for calling the FigureManagerNbAgg obj's underlying member method code with example usage: obj.get_javascript(cls, stream) and returns: output