In 1975, Australia had a government shutdown. This was resolved by firing all members of parliament and the prime minister and holding a special election for new members. There has not been a shutdown since.
Based on that incident, I propose that a law is enacted declaring that all current and future members of congress and presidents involved in a government shutdown during their term ineligible for reelection or election to any position in congress.
This will help to prevent using threats of government shutdown for political gain as doing so will ruin the politicians' careers. Also, to avoid party favoritism, the president would also be subject to the same penalty. Those penalized however would be able to finish their current term to give time to prepare new candidates for election.