title: github how to delete old ssh key on my mac?
body: <p>Hi I recently purchased a used mac for development, however when I try to push code from my mac to my github repository. I will be getting this error:<strong>Permission to myself/testuser.git denied to oldmacowner for example.</strong> </p>
  
  <p>I am wondering how to go about this. I think I need to delete the old ssh key that belongs to the oldmacuser and set up a new ssh key from github. Anyone have an idea of how to go about it? Thanks. </p>