Many Plotly Express functions accept a `color_continuous_scale` argument and many trace

types have a `colorscale` attribute in their schema. Plotly comes with a large number of

built-in continuous color scales, which can be referred to in Python code when setting the above arguments,

`go.Scatter(marker_colorscale=plotly.colors.sequential.Viridis)`. They can also be reversed by adding `_r` at the end

e.g. `"Viridis_r"` or `plotly.colors.sequential.Viridis_r`.