code: def trend(self, order=LINEAR):
          '''Override Series.trend() to return a TimeSeries instance.'''
          coefficients = self.trend_coefficients(order)
          x = self.timestamps
          trend_y = LazyImport.numpy().polyval(coefficients, x)
          return TimeSeries(zip(x, trend_y)f trend(self, order=LINEAR):
          '''Override Series.trend() to return a TimeSeries instance.'''
          coefficients = self.trend_coefficients(order)
          x = self.timestamps
          trend_y = LazyImport.numpy().polyval(coefficients, x)
          return TimeSeries(zip(x, trend_y))
docs: Override Series.trend() to return a TimeSeries instance.