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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 idx_sequence(self):
 """Indices of sentences when enumerating data set from batches. Useful when retrieving the correct order of sentences Returns ------- list List of ids ranging from 0 to #sent -1 """

        return [x[1] for x in sorted(zip(self._record, list(range(len(self._record)))))]