The figure above shows the plot of the points $(1,7)$, $(2,4)$, $(3,6)$, $(5,3)$, and $(6,8)$. Find a polynomial of degree 4 of the form $f(x) = a x^4 + b x^3 + c x^2 + d x + e$ whose graph passes through these points.

$f(x) =$

Hint: You may want to consider using a computer algebra system to assist in the computation.