Source: https://www.census.gov/geographies/mapping-files/time-series/geo/carto-boundary-file.html
Arguments
- level
Defaults to "county". Available options are: "cd116" (for congressional districts of the 116th Congress)
- resolution
Defaults to "500k", max available resolution. Available options are: "5m" and "20m"
- year
Defaults to 2018