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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 multi_click(self, locator, params=None, timeout=None):
 """ Presses left control or command button depending on OS, clicks and then releases control or command key. :param locator: locator tuple or WebElement instance :param params: (optional) locator parameters :param timeout: (optional) time to wait for element :return: None """

        platform = self.execute_script('return navigator.platform')
        multi_key = Keys.COMMAND if 'mac' in platform.lower() else Keys.LEFT_CONTROL
        self._click(locator, params, timeout, multi_key)