Uncaught TypeError: Object #<a Document> has no method 'write'?

When trying to include google visualization api into a page on google app engine, getting this error in the developer tools开发者_开发百科 console in Chrome: Uncaught TypeError: Object # has no method 'write'

In FF 3.5 the error is "n.write is not a function". A bit of a noob here and have no clue how to troubleshoot this. Any ideas?

Code can be found here: Google visualization api on app engine not working... (python)

In case anyone else has this issue - I messed up headers of the page generated by rendering with the same function I created for XML output.

Including this killed it: handler.response.headers["Content-Type"] = "text/xml"

If you are using JSF2 and XHTML facelets, you need to use:

<f:view contentType="text/html">
   <!-- page with charts here -->
</f:view>