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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 _set_text(self, value):
 """ set text at current working_index. Return whether it changed. """

        working_index = self.working_index
        working_lines = self._working_lines

        original_value = working_lines[working_index]
        working_lines[working_index] = value

        # Return True when this text has been changed.
        if len(value) != len(original_value):
            # For Python 2, it seems that when two strings have a different
            # length and one is a prefix of the other, Python still scans
            # character by character to see whether the strings are different.
            # (Some benchmarking showed significant differences for big
            # documents. >100,000 of lines.)
            return True
        elif value != original_value:
            return True
        return False