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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 history_backward(self, count=1):
 """ Move backwards through history. """

        self._set_history_search()

        # Go back in history.
        found_something = False

        for i in range(self.working_index - 1, -1, -1):
            if self._history_matches(i):
                self.working_index = i
                count -= 1
                found_something = True
            if count == 0:
                break

        # If we move to another entry, move cursor to the end of the line.
        if found_something:
            self.cursor_position = len(self.text)