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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 hover_on_element(driver, selector, by=By.CSS_SELECTOR):
 """ Fires the hover event for the specified element by the given selector. @Params driver - the webdriver object (required) selector - the locator (css selector) that is used (required) by - the method to search for the locator (Default: By.CSS_SELECTOR) """

    element = driver.find_element(by=by, value=selector)
    hover = ActionChains(driver).move_to_element(element)
    hover.perform()