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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_prep_value(self, value):
 """ Convert the value to a string so it can be stored in the database. """

        if value == "":
            return None
        if isinstance(value, (dict, list)):
            return self.serializer(value)
        return super(JSONField, self).get_prep_value(value)