code: def page_should_contain_text(self, text, loglevel='INFO'):
          
          if not self._is_text_present(text):
              self.log_source(loglevel)
              raise AssertionError("Page should have contained text '%s' "
                                   "but did not" % text)
          self._info("Current page contains text '%s'." % text)
docs: Verifies that current page contains `text`.
  
          If this keyword fails, it automatically logs the page source
          using the log level specified with the optional `loglevel` argument.
          Giving `NONE` as level disables logging.