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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 fix_e714(self, result):
 """Fix object identity should be 'is not' case."""

        (line_index, offset, target) = get_index_offset_contents(result,
                                                                 self.source)

        # to convert once 'is not' -> 'is'
        before_target = target[:offset]
        target = target[offset:]
        match_isnot = COMPARE_NEGATIVE_REGEX_THROUGH.search(target)
        isnot_pos_start, isnot_pos_end = 0, 0
        if match_isnot:
            isnot_pos_start = match_isnot.start(1)
            isnot_pos_end = match_isnot.end()
            target = '{}{} {}'.format(
                target[:isnot_pos_start], 'in', target[isnot_pos_end:])

        match = COMPARE_NEGATIVE_REGEX.search(target)
        if match:
            if match.group(3).startswith('is'):
                pos_start = match.start(1)
                new_target = '{5}{0}{1} {2} {3} {4}'.format(
                    target[:pos_start], match.group(2), match.group(3),
                    match.group(1), target[match.end():], before_target)
                if match_isnot:
                    # revert 'is' -> 'is not'
                    pos_start = isnot_pos_start + offset
                    pos_end = isnot_pos_end + offset - 4     # len('not ')
                    new_target = '{}{} {}'.format(
                        new_target[:pos_start], 'is not', new_target[pos_end:])
                self.source[line_index] = new_target