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Potassium-doped barium bismuth oxide ($Ba_{1-x} K_x Bi O_3$), is a famous high temperature superconductor, discovered in the late 1980s~\cite{Sleight_1975, Cava_1988}. Its parent compound, BaBiO$_3$, has a distorted perovskite structure, with a band gap of $\sim 0.2$~eV~\cite{Sleight_1975}. Doping the material, with K for example, suppresses the structural distortions and makes the material superconducting, reaching a transition temperature of nearly 30~K at optimal doping. DFT does not describe the insulating character of the parent compound. Conventional DFT estimates of the electron phonon coupling $\lambda$ within Migdal-Eliasberg theory give a value of 0.34 in the doped compound, too small to account for its superconductivity~\cite{Meregalli_1998}.  Examining the effect of correlations, we found that $\lambda$ is substantially enhanced relative to its DFT estimate to a value of nearly $1.0$, and that this enhancement is responsible for superconductivity in BaBiO$_3$~\cite{Yin_2013}. We argue that correlations similarly enhance the electron phonon coupling in other materials proximate to an insulating state, accounting for superconductivity in systems such as %  HfNCl, borocarbides and buckminsterfullerenes. For these materials the most important type of correlation that needs to be treated is the static  ( in the solid state physicist convention) correlations. Hence a GW, or a hybrid DFT calcuation is enough