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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 runs(self, date: datetime.date = None, days: int = None) -> list: """Return all program runs for X days from Y date."""

        endpoint = 'watering/past'

        if date and days:
            endpoint = '{0}/{1}/{2}'.format(
                endpoint, date.strftime('%Y-%m-%d'), days)

        data = await self._request('get', endpoint)
        return data['pastValues']