Find the inverse Laplace Transform f(t)

$\displaystyle F \left( s \right) ={\frac {s \left( 1-{e}^{-2\,s} \right) }{{s}^{2}+{

\pi }^{2}}}

$

The top half looks like the inverse staircase transform, [[a/t]], but that doesnt explain the denominator looking like the bottom of a sin transform ... not sure how to tackle this.