How to evaluate the code inside the MuPad notebook?? to find the Euler Phi value of given input

x=5; x=sym(x); nb=mupad('phi.mn'); setVar(nb,x); z=getVar(nb,'z');

content of file phi.mn is [z := numlib::phi(x);

The output of z=getVar(nb,'z') gives z=z as output :(