code: function (arr) {
          if (!_.isArray(arr)) {
              return;
          }
  
          var obj = {},
              key,
              val,
              i,
              ii;
  
          for (i = 0, ii = arr.length; i < ii; i += 2) {
              key = arr[i];
              val = arr[i + 1];
  
              if (_.has(obj, key)) {
                  !_.isArray(obj[key]) && (obj[key] = [obj[key]]);
                  obj[key].push(val);
              }
              else {
                  obj[key] = val;
              }
          }
  
          return obj;
      }
docs: Converts an array of sequential pairs to an object.
  
  @param arr
  @returns {{}}
  
  @example
  ['a', 'b', 'c', 'd'] ====> {a: 'b', c: 'd' }