'Verify label is rendered correctly.
Arguments:
xpath (str): xpath expression for label element
aria_label (bool): check aria-label attribute value'

def assert_label(self, xpath=None, aria_label=False):

    labels = [{'actual': 'You    see,    but    you    do    not    observe.    The    distinction    is    clear.', 'expected': 'You    see,    but    you    do    not    observe.    The    distinction    is    clear.'}, {'actual': 'I    choose    to    have    <mark>faith</mark>    because    without    that,    I    have    <em>nothing</em>.', 'expected': 'I    choose    to    have    faith    because    without    that,    I    have    nothing.'}]
    response_data = {'response_data': {'descriptions': {}, 'label': ''}}
    self.context.update(response_data)
    for label in labels:
        self.context['response_data']['label'] = label['actual']
        xml = self.render_to_xml(self.context)
        if aria_label:
            self.assert_has_xpath(xml, ("//*[@aria-label='%s']" % label['expected']), self.context)
        else:
            element_list = xml.xpath(xpath)
            self.assertEqual(len(element_list), 1)
            self.assertEqual(stringify_children(element_list[0]), label['actual'])
