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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:
 async def get_or_create(self, model_, defaults=None, **kwargs):
 """Try to get an object or create it with the specified defaults. Return 2-tuple containing the model instance and a boolean indicating whether the instance was created. """

        try:
            return (await self.get(model_, **kwargs)), False
        except model_.DoesNotExist:
            data = defaults or {}
            data.update({k: v for k, v in kwargs.items() if '__' not in k})
            return (await self.create(model_, **data)), True