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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 _ensure_click(self):
 """Ensures a click gets made, because Selenium can be a bit buggy about clicks This method gets added to the selenium element returned in '__ensure_element_by_xpath'. We should probably add it to more selenium methods, such as all the 'find**' methods though. I wrote this method out of frustration with chromedriver and its problems with clicking items that need to be scrolled to in order to be clickable. In '__ensure_element_by_xpath' we scroll to the item before returning it, but chrome has some problems if it doesn't get some time to scroll to the item. This method ensures chromes gets enough time to scroll to the item before clicking it. I tried SEVERAL more 'correct' methods to get around this, but none of them worked 100% of the time (waiting for the element to be 'clickable' does not work). """


    # We ensure the element is scrolled into the middle of the viewport to ensure that
    # it is clickable. There are two main ways an element may not be clickable:
    #   - It is outside of the viewport
    #   - It is under a banner or toolbar
    # This script solves both cases
    script = ("var viewPortHeight = Math.max("
              "document.documentElement.clientHeight, window.innerHeight || 0);"
              "var elementTop = arguments[0].getBoundingClientRect().top;"
              "window.scrollBy(0, elementTop-(viewPortHeight/2));")
    self.parent.execute_script(script, self)  # parent = the webdriver

    for _ in range(10):
        try:
            self.click()
            return
        except WebDriverException as e:
            exception_message = str(e)
            time.sleep(0.2)
    raise WebDriverException(
        "Couldn't click item after trying 10 times, got error message: \n{}".format(
            exception_message
        )
    )