Numpy Python并行化扩展与串行计算相同

I am trying to show some sort of improvement by parallelizing a toy piece of code in Python before I attempt to parallelize my main program. The approach I have decided to take is to perform four matrix inversions in parallel, and then perform the same matrix inversion one time and multiply by four to get an estimate for how long the problem would take to finish in serial. I understand there will be some constant overhead with parallelizing, but as a first order approximation this should be fine for my purposes.I am trying to show some sort of improvement by