code: def print_cyjs_context(self):
          
          context = self._context
          context_str = json.dumps(context, indent=1, sort_keys=True)
          return context_str
docs: Return a list of node names and their respective context.
  
          Returns
          -------
          cyjs_str_context : str
              A json string of the context dictionary. e.g. -
              {'CCLE' : {'bin_expression' : {'cell_line1' : {'gene1':'val1'} },
              'bin_expression' : {'cell_line' : {'gene1':'val1'} }
              }}