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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_rank(self, team):
 """ Find the team's rank when applicable. If a team is ranked, it will showup in a separate <span> tag with the actual rank embedded between parentheses. When a team is ranked, the integer value representing their ranking should be returned. For teams that are not ranked, None should be returned. Parameters team : PyQuery object A PyQuery object of a team's HTML tag in the boxscore. Returns ------- int Returns an integer representing the team's ranking when applicable, or None if the team is not ranked. """

        rank = None
        rank_field = team('span[class="pollrank"]')
        if len(rank_field) > 0:
            rank = re.findall(r'\(\d+\)', str(rank_field))[0]
            rank = int(rank.replace('(', '').replace(')', ''))
        return rank