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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 wait_for(self, wait_for):
 """ Wait for callback to return True. Simply returns if wait_for condition has been met, raises TimeoutExpired otherwise and kills the process. :param callback wait_for: callback to call :raises: mirakuru.exceptions.TimeoutExpired :returns: itself :rtype: SimpleExecutor """

        while self.check_timeout():
            if wait_for():
                return self
            time.sleep(self._sleep)

        self.kill()
        raise TimeoutExpired(self, timeout=self._timeout)