1  module.exports = extend
 2  
 3  var hasOwnProperty = Object.prototype.hasOwnProperty;
 4  
 5  function extend() {
 6      var target = {}
 7  
 8      for (var i = 0; i < arguments.length; i++) {
 9          var source = arguments[i]
10  
11          for (var key in source) {
12              if (hasOwnProperty.call(source, key)) {
13                  target[key] = source[key]
14              }
15          }
16      }
17  
18      return target
19  }