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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 parse(self, data):
 """ Converts a BMX6 b6m JSON to a NetworkX Graph object which is then returned. """

        # initialize graph and list of aggregated nodes
        graph = self._init_graph()
        if len(data) != 0:
            if "links" not in data[0]:
                raise ParserError('Parse error, "links" key not found')
        # loop over topology section and create networkx graph
        # this data structure does not contain cost information, so we set it as 1
        for node in data:
            for link in node['links']:
                cost = (link['txRate'] + link['rxRate']) / 2.0
                graph.add_edge(node['name'],
                               link['name'],
                               weight=cost,
                               tx_rate=link['txRate'],
                               rx_rate=link['rxRate'])
        return graph