Trying to have 3 variables that get randomly assigned numbers that add up to 100 [duplicate]

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• Generate multiple random numbers to equal a value in python 6 answers

So I'm trying to make a program that has 3 variables a, b, and c (these stand for contestants on a made up talent show) I don't know how to make it randomly assign values but have it that together the 3 numbers add up to 100. this is what I have so far.