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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 _serialize_data(self, my_dict):
 """ Serialize a Dictionary into JSON """

        new_dict = {}
        for item in my_dict:
            if isinstance(my_dict[item], datetime):
                new_dict[item] = my_dict[item].strftime('%Y-%m-%d%H:%M:%S')
            else:
                new_dict[item] = str(my_dict[item])

        return json.dumps(new_dict)