  A new version of the geometry inside a black hole is proposed, on the grounds
of an idea given by Doran et al. The spacetime is still time dependent and is a
solution of Einstein's equations with a stress tensor corresponding to an
anisotropic fluid. The energy density of the fluid is proportional to $1/t^{2}$
as in many dark energy models and the Brown-York quasilocal energy of the black
hole interior equals its mass $m$.
