code: function isArguments(value) {
        var str = _toString.call(value);
        var result = str === '[object Arguments]';
        if (!result) {
          result = str !== '[object Array]' &&
            value !== null &&
            typeof value === 'object' &&
            typeof value.length === 'number' &&
            value.length >= 0 &&
            _toString.call(value.callee) === '[object Function]';
        }
        return result;
      }
docs: taken directly from https://github.com/ljharb/is-arguments/blob/master/index.js can be replaced with require('is-arguments') if we ever use a build process instead