old_contents: (function(ext) {
      // Cleanup function when the extension is unloaded
      ext._shutdown = function() {};
  
      // Status reporting code
      // Use this to report missing hardware, plugin or unsupported browser
      ext._getStatus = function() {
          return {status: 2, msg: 'Ready'};
      };
  
  	ext.my_first_block = function(string) {
  		alert(string);
      };
  	
  	    ext.power = function(base, exponent) {
          return Math.pow(base,exponent);
      };
  
  	
      // Block and block menu descriptions
      var descriptor = {
          blocks: [
  			['', 'My First Block', 'my_first_block'],
  			['r', '%n ^ %n', 'power', 2, 3],
          ]
      };
  
      // Register the extension
      ScratchExtensions.register('Kinect2Scratch', descriptor, ext);
  })({});
new_contents: (function(ext) {
      // Cleanup function when the extension is unloaded
      ext._shutdown = function() {};
  
      // Status reporting code
      // Use this to report missing hardware, plugin or unsupported browser
      ext._getStatus = function() {
          return {status: 2, msg: 'Ready'};
      };
  
  	ext.my_first_block = function() {
  		alert("Hello!");
      };
  	
  	    ext.power = function(base, exponent) {
          return Math.pow(base,exponent);
      };
  
  	
      // Block and block menu descriptions
      var descriptor = {
          blocks: [
  			['', 'My First Block', 'my_first_block'],
  			['r', '%n ^ %n', 'power', 2, 3],
          ]
      };
  
      // Register the extension
      ScratchExtensions.register('Kinect2Scratch', descriptor, ext);
  })({});
subject: Modify things