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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def save_json(self, fname_prefix='model'):
 """Save the assembled Cytoscape JS network in a json file. This method saves two files based on the file name prefix given. It saves one json file with the graph itself, and another json file with the context. Parameters fname_prefix : Optional[str] The prefix of the files to save the Cytoscape JS network and context to. Default: model """

        cyjs_str = self.print_cyjs_graph()
        # outputs the graph
        with open(fname_prefix + '.json', 'wb') as fh:
            fh.write(cyjs_str.encode('utf-8'))
        # outputs the context of graph nodes
        context_str = self.print_cyjs_context()
        with open(fname_prefix + '_context.json', 'wb') as fh:
            fh.write(context_str.encode('utf-8'))