Nothing
      library("ggplot2")
p <- ggplot(mtcars, aes(x = wt, y = mpg, colour = factor(gear))) +
  geom_point() +
  facet_wrap(~am) +
  geom_smooth(method = "lm", se = FALSE) +
  scale_color_fivethirtyeight() +
  theme_fivethirtyeight()
p
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