Make a 3D scatter plot using python

I want to use Python to draw a 3D plot with the following data. I have a lot of data that I want to visualize in a 3D plot. However, when I use Matplotlib to create the plot with circular markers (marker='o'), the resulting plot consists of circles.

Example Diagram

How can I make these data points appear as 3D spheres? I also need to control their colors and sizes. I hope to get some help.