Mapping enhancements

[mads14]

@papajohn @SamLau95
Hi! I'm the GSI for the smart cities connector course. I talked to Sam about the mapping tool this morning. I was wondering if we could add a method to overlay map features over an existing map. Basically the issue I ran into is that after I create a map I may want to add markers or labels to the map, and so far there's not an easy way to do that:

I wrote the following method that seems to do the trick. Could this be added to the Map tool?
The only other issue with the function is that in my implementation I edit the Map._folium_map directly. It might be nice if we copy and return a new Map object instead of modifying the existing Map in place. I couldn't figure out the best way to do this. If you have time, it would be great if you could take a look. Let me know if you have any questions.

Best,
Maddie

def overlay(feature, ds_map, color='Blue', opacity=.6):
'''
feature can be a table of map features, a list of map features,
a Map, or a Region. The features will be drawn on the existing
Map (ds_map).
'''

if type(feature) == Table:
    # if table of features e.g. Table.from_records(taz_map.features)
    if 'feature' in feature:
        feature = feature['feature']

    # if marker table e.g. table with columns: latitudes,longitudes,popup,color,radius
    else:
        feature = Circle.map_table(feature)

if type(feature) in [list, np.ndarray]:
    for f in feature:
        f._attrs['fill_color'] = color
        f._attrs['fill_opacity'] = opacity
        f.draw_on(ds_map._folium_map)

elif type(feature) == Map:
    for i in range(len(feature._features)):
        f = feature._features[i]
        f._attrs['fill_color'] = color
        f._attrs['fill_opacity'] = opacity
        f.draw_on(ds_map._folium_map)
elif type(feature) == Region:
    feature._attrs['fill_color'] = color
    feature._attrs['fill_opacity'] = opacity
    feature.draw_on(ds_map._folium_map)
return ds_map