Write a script $($using a single for loop$)$ that generates the following $3$D random walk $(1000$ steps$)$:

each step$-$size along x is $-1,0,$ or $1.$

each step$-$size along y is $-1$ or $1.$

each step$-$size along z is $-2$ or $2.$

The vector that stores the x$-$position should be called x; the vector that stores the y$-$position should be called y; the vector that stores the z$-$position should be called z$.$

The marker starts its motion at x$(1)=0,$ y$(1)=0,$ and z$(1)=0$