I tried to build PyTorch from the github. The instruction said that I need to install magma-cuda80. But I already installed cuda80 which I needed to use pytorch library.  cuda80 seems to be much up to date than magma-cuda80 in anaconda repository. What is a difference between cuda80 and magma-cuda80. Do I need the magma instead of just cuda80 to compile pytrorch from the source?