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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 prepare_value_for_storage(self, value, pk):
 """Prepare the value to be stored in the zset We'll store the value and pk concatenated. For the parameters, see BaseRangeIndex.prepare_value_for_storage """

        value = super(TextRangeIndex, self).prepare_value_for_storage(value, pk)
        return self.separator.join([value, str(pk)])