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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 send_keys(self, *keys_to_send):
 """ Sends keys to current focused element. :Args: - keys_to_send: The keys to send. Modifier keys constants can be found in the 'Keys' class. """

        typing = keys_to_typing(keys_to_send)
        if self._driver.w3c:
            for key in typing:
                self.key_down(key)
                self.key_up(key)
        else:
            self._actions.append(lambda: self._driver.execute(
                Command.SEND_KEYS_TO_ACTIVE_ELEMENT, {'value': typing}))
        return self