title: Runge-Kutta(RK4) for stiff IVP
body: <p>I need a solver of stiff Inital-Value Problems (IVP) in python exploiting RK4 preferably explicit. I have been searching for past few days but could not find it. Following are my queries:</p>
  
  <ul>
  <li>Does the solver, i.e. any module, exist?</li>
  <li>If no, will it be reasonable to code one? I am asking this because I can't find any reference for using RK4-explicit for stiff problems.</li>
  </ul>