Drawing pie chart on heatmap

Hello, everyone. Could you give me a clue about plots, I am working with the heatmap and would like to draw in each cell a pie chart. The circle of a pie chart could be divided into n number of colors. Is there any way to draw such visualization?
The example is here:

there is add_traceS funtion, which allows to add several traces without redrawing every time. That helps a lot!