Your browser does not seem to support JavaScript. As a result, your viewing experience will be diminished, and you have been placed in read-only mode.
Please download a browser that supports JavaScript, or enable it if it's disabled (i.e. NoScript).
I found the solution (I already had this problem but I couldn't remember the right code)
mat [c4d.MATERIAL_TRANSPARENCY_COLOR] = c4d.Vector (1.0, 1.0, 1.0) #color white mat.Update (True, True)
I found the solution to my problem, on the internet, with code samples: https://www.c4dcafe.com/ipb/forums/topic/101805-materials-and-shaders-with-python/