docs: def _add_ssh_key(ret):
      '''
      Setups the salt-ssh minion to be accessed with salt-ssh default key
      '''
      priv = None
      if __opts__.get('ssh_use_home_key') and os.path.isfile(os.path.expanduser('~/.ssh/id_rsa')):
          priv = os.path.expanduser('~/.ssh/id_rsa')
      else:
          priv = __opts__.get(
              'ssh_priv',
              os.path.abspath(os.path.join(
                  __opts__['pki_dir'],
                  'ssh',
                  'salt-ssh.rsa'
              ))
          )
      if priv and os.path.isfile(priv):
          ret['priv'] = priv