map.choropleth(geo_path=countries, data=to_plot,
columns=['CountryCode', 'Value'],
key_on='feature.id',
fill_color='YlGnBu', fill_opacity=0.7, line_opacity=.5)
I am getting the error below, and the code is copied verbatim (except for the exclusion of legend title) from a source that works, so I'm at a loss
JSONDecodeError: Expecting value: line 7 column 1 (char 6)
Thanks