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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 get_json(self):
 """Create JSON for CNA port. :returns: JSON for CNA port as follows: { "@PortIdx":1, "PortEnable":{ }, "Functions":{ } } """

        port = self.get_basic_json()
        port['Functions'] = {
            'Function': [f.get_json() for f in self.functions.values()]
        }
        return port