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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 next(self):
 """ Return the next window """

        next_index = (self.index + 1) % len(self._browser.driver.window_handles)
        next_handle = self._browser.driver.window_handles[next_index]
        return Window(self._browser, next_handle)