Evaluate the integral using the Fundamental Theorem of Line Integrals.
Evaluate $\quad \int_{C} \mathbf{F} \cdot d r, \quad$ where $f(x, y, z)=\cos (\pi x)+\sin (\pi y)-x y z$ and $C$ is any path that starts at $\left(1, \frac{1}{2}, 2\right)$ and ends at (2,1,-1)