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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 data for slot. :returns: JSON data for slot as follows: { "@SlotIdx":0, "OnboardControllers":{ "OnboardController": [ ] }, "AddOnCards":{ "AddOnCard": [ ] } } """

        json = self.get_basic_json()
        if self.onboard_cards:
            json['OnboardControllers'] = {
                'OnboardController':
                    [c.get_json() for c in self.onboard_cards.values()]
            }
        if self.addon_cards:
            json['AddOnCards'] = {
                'AddOnCard': [c.get_json() for c in self.addon_cards.values()]
            }
        return json