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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_until_element_not_visible(webdriver, locator_lambda_expression, timeout=WTF_TIMEOUT_MANAGER.NORMAL, sleep=0.5):
 """ Wait for a WebElement to disappear. Args: webdriver (Webdriver) - Selenium Webdriver locator (lambda) - Locator lambda expression. Kwargs: timeout (number) - timeout period sleep (number) - sleep period between intervals. """

        # Wait for loading progress indicator to go away.
        try:
            stoptime = datetime.now() + timedelta(seconds=timeout)
            while datetime.now() < stoptime:
                element = WebDriverWait(webdriver, WTF_TIMEOUT_MANAGER.BRIEF).until(
                    locator_lambda_expression)
                if element.is_displayed():
                    time.sleep(sleep)
                else:
                    break
        except TimeoutException:
            pass