code: function last(array, n, guard) {
      if (array) {
        var length = array.length;
        return (n == undefined || guard) ? array[length - 1] : slice.call(array, -n || length);
      }
    }
docs: Gets the last value of the `array`. Pass `n` to return the lasy `n` values
  of the `array`.
  
  @static
  @memberOf _
  @category Arrays
  @param {Array} array The array to query.
  @param {Number} [n] The number of elements to return.
  @param {Object} [guard] Internally used to allow this method to work with
  others like `_.map` without using their callback `index` argument for `n`.
  @returns {Mixed} Returns the last value or an array of the last `n` values
  of `array`.
  @example
  
  _.last([3, 2, 1]);
  // => 1