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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 close_driver(self):
 """ Close current running instance of Webdriver. Usage:: driver = WTF_WEBDRIVER_MANAGER.new_driver() driver.get("http://the-internet.herokuapp.com") WTF_WEBDRIVER_MANAGER.close_driver() """

        channel = self.__get_channel()
        driver = self.__get_driver_for_channel(channel)
        if self.__config.get(self.REUSE_BROWSER, True):
            # If reuse browser is set, we'll avoid closing it and just clear out the cookies,
            # and reset the location.
            try:
                driver.delete_all_cookies()
                # check to see if webdriver is still responding
                driver.get("about:blank")
            except:
                pass

        if driver is not None:
            try:
                driver.quit()
            except:
                pass

            self.__unregister_driver(channel)
            if driver in self.__registered_drivers[channel]:
                self.__registered_drivers[channel].remove(driver)

            self.webdriver = None