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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 save(self, force_insert=False):
 """ Save the model and any related many-to-many fields. :param force_insert: Should the save force an insert? :return: Number of rows impacted, or False. """

        delayed = {}
        for field, value in self.data.items():
            model_field = getattr(type(self.instance), field, None)

            # If this is a many-to-many field, we cannot save it to the instance until the instance
            # is saved to the database. Collect these fields and delay the setting until after
            # the model instance is saved.
            if isinstance(model_field, ManyToManyField):
                if value is not None:
                    delayed[field] = value
                continue

            setattr(self.instance, field, value)

        rv = self.instance.save(force_insert=force_insert)

        for field, value in delayed.items():
            setattr(self.instance, field, value)

        return rv