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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def deliver_dashboard(schedule):
 """ Given a schedule, delivery the dashboard as an email report """

    dashboard = schedule.dashboard

    dashboard_url = _get_url_path(
        'Superset.dashboard',
        dashboard_id=dashboard.id,
    )

    # Create a driver, fetch the page, wait for the page to render
    driver = create_webdriver()
    window = config.get('WEBDRIVER_WINDOW')['dashboard']
    driver.set_window_size(*window)
    driver.get(dashboard_url)
    time.sleep(PAGE_RENDER_WAIT)

    # Set up a function to retry once for the element.
    # This is buggy in certain selenium versions with firefox driver
    get_element = getattr(driver, 'find_element_by_class_name')
    element = retry_call(
        get_element,
        fargs=['grid-container'],
        tries=2,
        delay=PAGE_RENDER_WAIT,
    )

    try:
        screenshot = element.screenshot_as_png
    except WebDriverException:
        # Some webdrivers do not support screenshots for elements.
        # In such cases, take a screenshot of the entire page.
        screenshot = driver.screenshot()  # pylint: disable=no-member
    finally:
        destroy_webdriver(driver)

    # Generate the email body and attachments
    email = _generate_mail_content(
        schedule,
        screenshot,
        dashboard.dashboard_title,
        dashboard_url,
    )

    subject = __(
        '%(prefix)s %(title)s',
        prefix=config.get('EMAIL_REPORTS_SUBJECT_PREFIX'),
        title=dashboard.dashboard_title,
    )

    _deliver_email(schedule, subject, email)