title: Parameter optimization for multi-class Support Vector Machine with scikit-learn
body: <p>I am trying to use SVC class in scikit-learn library to solve a multi-class classification problem. I am interested in one-vs-one strategy. And I want to
  optimize hyper-parameters (C and gamma) for each pair of classes. But I don't 
  know how to do that in scikit-learn. How can I do that? 
  Thank you very much.</p>