title: Packaging py2app app with productbuild
body: <p>I am using pyobjc to create my mac app. I generated the .app executable using py2app using the command <code>python setup.py py2app</code>. I am now trying to submit this app to the app store. In order to do this, I need to convert it into a .pkg file. I am doing this using the command <code>productbuild --content dist/MaApp.app dist/MyApp.pkg</code>. The .pkg file is successfully created and on double clicking it, I am able to install my application. I even get the 'Installation was successful' screen of the installer. However, I am not able to find the installed application at the end of this process. I am not getting the usual screen which asks the user to drag the app to the application folder. Do I need to make any modifications to the build process to achieve this?</p>
  
  <p><img src="https://i.stack.imgur.com/G6xAj.png" alt="enter image description here"></p>
  
  <p><img src="https://i.stack.imgur.com/0BDPr.jpg" alt="enter image description here"></p>