Highlighting States With Cartopy

import matplotlib.patches as mpatches
import matplotlib.pyplot as plt
import shapely.geometry as sgeom

import cartopy.crs as ccrs
import cartopy.io.shapereader as shpreader

import pandas as pd

# derived from this example: https://scitools.org.uk/cartopy/docs/v0.15/examples/hurricane_katrina.html

def plot_states(df,projection,colors,annotation,title,edgecolor):

    ax = plt.axes([0, 0, 1, 1],
                  projection=projection)
    ax.background_patch.set_visible(False)
    ax.outline_patch.set_visible(False)
    ax.set_extent([-125, -66.5, 20, 50], ccrs.Geodetic())

    shapename = 'admin_1_states_provinces_lakes_shp'
    shpfilename = shpreader.natural_earth(resolution='110m',
                                         category='cultural', name=shapename)

    reader = shpreader.Reader(shpfilename)
    states = reader.records()
    values = list(df[title].unique())


    for state in states:
        attribute = 'name'
        name = state.attributes[attribute]

        # get classification
        try:
            classification = df.loc[state.attributes[attribute]][title]
        except:
            pass

        ax.add_geometries(state.geometry, ccrs.PlateCarree(),
                          facecolor=(colors[values.index(classification)]),
                          label=state.attributes[attribute],
                          edgecolor='#FFFFFF',
                          linewidth=.25)

    # legend
    import matplotlib.patches as mpatches
    handles = []
    for i in range(len(values)):
        handles.append(mpatches.Rectangle((0, 0), 1, 1, facecolor=colors[i]))
        plt.legend(handles, values,
                   loc='lower left', bbox_to_anchor=(0.025, -0.0), 
                   fancybox=True, frameon=False, fontsize=5)

    # annotate
    ax.annotate(annotation, xy=(0, 0),  xycoords='figure fraction',
            xytext=(0.0275, -0.025), textcoords='axes fraction',
            horizontalalignment='left', verticalalignment='center', fontsize=4,
            )

    plt.title(title, fontsize=8)

    title = title+'.png'
    plt.savefig(title, bbox_inches='tight', pad_inches=.2, dpi=300)
    print('Saved: {}'.format(title))


def main():
    # df = pd.read_csv('states.csv')
    df = pd.read_csv('states.csv', index_col='State')

    # States Visited
    projection = ccrs.LambertConformal()
    title = 'States Visited'
    colors = ['#71a2d6','#DDDDDD']
    annotation = ''
    plot_states(df,projection,colors,annotation,title,edgecolor='white')

    # 13 Original Colonies
    projection = ccrs.LambertConformal()
    title = '13 Original Colonies'
    colors = ['#DDDDDD','#71a2d6']
    annotation = ''
    plot_states(df,projection,colors,annotation,title,edgecolor='white')

    print('Done.\n')


if __name__ == '__main__':
    main()