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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 index_iterator(self):
 """ Generator that resumes from same index, or restarts from sent index. """

        idx = 0  # index
        while idx < self.number_intervals:
            new_idx = yield idx
            idx += 1
            if new_idx:
                idx = new_idx - 1