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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 get_error_page(self):
 """ Method returning error page. Should return string. By default it find element with class ``error-page`` and returns text of ``h1`` header. You can change this method accordingly to your app. Error page returned from this method is used in decorators :py:func:`.expected_error_page` and :py:func:`.allowed_error_pages`. """

        try:
            error_page = self.get_elm(class_name='error-page')
        except NoSuchElementException:
            pass
        else:
            header = error_page.get_elm(tag_name='h1')
            return header.text