...ah, I think I get what you want. There is a 99% probability that this is not a good idea, but I will give you the code to do what I think you're asking for anyway:
First you need to change this line:
variables = ['x','y']
(since you want the variable names here, not the values)
Now in order for the variable x
to be assigned, one way to do that is:
locals()[variables[0]] = data[0]