def render_external_question(url, frame_height=0):
    """
    Renders a URL within an ExternalQuestion XML object for use as a task.
    :param url: The URL of the task to display to Workers
    :param frame_height: Frame height to use for the Worker viewport, zero by default to use the whole window
    :return: The rendered ExternalQuestion XML string
    """
    return '''
    <ExternalQuestion 
            xmlns="http://mechanicalturk.amazonaws.com/AWSMechanicalTurkDataSchemas/2006-07-14/ExternalQuestion.xsd">
        <ExternalURL>{}</ExternalURL><FrameHeight>{}</FrameHeight>
    </ExternalQuestion>'''.format(url, frame_height)