code: def get_visualizations():
      
      if not hasattr(g, 'visualizations'):
          g.visualizations = {}
          for VisClass in _get_visualization_classes():
              vis = VisClass(get_model())
              g.visualizations[vis.__class__.__name__] = vis
      return g.visualizations
docs: Get the available visualizations from the request context.  Put the
      visualizations in the request context if they are not yet there.
  
      Returns:
          :obj:`list` of instances of :class:`.BaseVisualization` or
          derived class