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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 reduce(self, start=0, end=None):
 """Returns result of applying `self.operation` to a contiguous subsequence of the array. self.operation( Parameters start: int beginning of the subsequence end: int end of the subsequences Returns ------- reduced: obj result of reducing self.operation over the specified range of array elements. """

        if end is None:
            end = self._capacity - 1
        if end < 0:
            end += self._capacity
        return self._reduce_helper(start, end, 1, 0, self._capacity - 1)