Return a dictionary with links to supplement files (pdf, csv, zip,
        ipynb, html and so on) extracted from peer assignment.

        @param element_id: Element ID to extract files from.
        @type element_id: str

        @return: @see CourseraOnDemand._extract_links_from_text

def extract_links_from_peer_assignment(self, element_id):
        """
        Return a dictionary with links to supplement files (pdf, csv, zip,
        ipynb, html and so on) extracted from peer assignment.

        @param element_id: Element ID to extract files from.
        @type element_id: str

        @return: @see CourseraOnDemand._extract_links_from_text
        """
        logging.debug(
            'Gathering supplement URLs for element_id <%s>.', element_id)

        try:
            # Assignment text (instructions) contains asset tags which describe
            # supplementary files.
            text = ''.join(self._extract_peer_assignment_text(element_id))
            if not text:
                return {}

            supplement_links = self._extract_links_from_text(text)
            instructions = (IN_MEMORY_MARKER + self._markup_to_html(text),
                            'peer_assignment_instructions')
            extend_supplement_links(
                supplement_links, {IN_MEMORY_EXTENSION: [instructions]})
            return supplement_links
        except requests.exceptions.HTTPError as exception:
            logging.error('Could not download peer assignment %s: %s',
                          element_id, exception)
            if is_debug_run():
                logging.exception('Could not download peer assignment %s: %s',
                                  element_id, exception)
            return None