In the following example, how do I change the legend titles? For example, level becomes Level; .model becomes Forecast.
library(fpp3)
us_change %>%
model(model1 = ARIMA(Consumption ~ PDQ(0,0,0)),
model2 = ARIMA(Consumption ~ PDQ(1,0,0))) %>%
forecast(h = 36) %>%
autoplot(us_change)

Created on 2020-11-24 by the reprex package (v0.3.0)