Use the HeatmapViz class to generate a heat map from the data:

measure = 'Female Population'
heatmap_color_stops = create_color_stops([0.01, 0.25, 0.5, 0.75, 1], colors='PuRd')
heatmap_radius_stops = [[0, 3], [14, 100]] 
color_breaks = [round(tract_poly[measure].quantile(q=x*0.1), 2) for x in range(2,10)]
color_stops = create_color_stops(color_breaks, colors='Spectral')
heatmap_weight_stops = create_weight_stops(color_breaks) 
vizheat = HeatmapViz('tracts_points2.geojson', 
                  access_token=token,
                  weight_property = "Female Population",
                  weight_stops = heatmap_weight_stops,
                  color_stops = heatmap_color_stops,
                  radius_stops = heatmap_radius_stops,
                  opacity = 0.8,
                  center=(-122, 37.78),
                  zoom=7,
                  below_layer='waterway-label'
                 )
vizheat.show()