Is this a function composed of multiple functions, i.e a function of a function? and how to solve it! //multivariable analysis

Question

So i am given the following:
$f(x,y)=x^y$
$u(x,y)=x+lny$
$v(x,y)= x-lny$
and suppose that a new function defined as:
$g(u,v)=f(x(u,v),y(u,v))$
and i am asked to find the partial derivative at a two points one of which is $∂g(3,3)/∂u$
i am more interested in the way of thinking and approaching the question rather than the solution. Thanks a lot in advance :)