how to express mupad piecewise in a natural form ?

I have the unit step function: u0:= piecewise([-infinity < t and t < 0,0],[0 < t and t < infinity,1]):

Now I want to plot It at some point: T:=1:; plot(u0|t=t-T/2);

This works but when I use more natural expression It plots only the step function: T:=1:; plot(u0(t-T/2));

it simply plots the symbolic function

Is there any way to use the more simpler form when plotting the modified step function ?