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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 zcount(self, name, score_start, score_end):
 """ Returns the number of elements in the sorted set at key ``name`` with a score between ``score_start`` and ``score_end``. Like **Redis.ZCOUNT** .. note:: The range is [``score_start``, ``score_end``] :param string name: the zset name :param int score_start: The minimum score related to keys(included), empty string ``''`` means -inf :param int score_end: The maximum score(included) related to keys, empty string ``''`` means +inf :return: the number of keys in specified range :rtype: int 3 6 0 """
        
        score_start = get_integer_or_emptystring('score_start', score_start)
        score_end = get_integer_or_emptystring('score_end', score_end)
        return self.execute_command('zcount', name, score_start, score_end)