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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 _extract_value_from_storage(self, string):
 """Taking a string that was a member of the zset, extract the value and pk Parameters string: str The member extracted from the sorted set Returns ------- tuple Tuple with the value and the pk, extracted from the string """

        parts = string.split(self.separator)
        pk = parts.pop()
        return self.separator.join(parts), pk