code: function parseArguments(opts, callback) {
    if ('function' === typeof opts) {
      callback = opts
      opts = {}
    }
  
    opts = opts || {}
    opts.callback = callback
  
    return opts
  }
docs: /* -------------------------------------------------------------------------- 
  Parse options, arguments juggling.
  
  @param  {object} opts
  @param  {function} callback
  @return {object}