selenium doesn't set downloaddir in FirefoxProfile

Question

i want to auto download files and save them in directory, everything is done but firefox stills save files in User download folder e.g. C:\users\root\Downloads

the function in class PyWebBot

@staticmethod
def FirefoxProfile(path, handlers):
    from selenium import webdriver

    profile = webdriver.FirefoxProfile()
    profile.set_preference("browser.download.folderList",1)
    profile.set_preference("browser.download.manager.showWhenStarting",False)
    profile.set_preference("browser.download.dir", path)
    profile.set_preference("browser.download.downloadDir", path)
    profile.set_preference("browser.download.defaultFolder", path)
    profile.set_preference("browser.helperApps.alwaysAsk.force", False)
    profile.set_preference("browser.helperApps.neverAsk.saveToDisk", handlers)
    profile.set_preference("pdfjs.disabled", True)
    profile.update_preferences()

    return profile

then

 def setUp(self):
        self.profile = PyWebBot.FirefoxProfile(config['downloads'], config['handlers'])
        self.driver = webdriver.Firefox(self.profile)
    ...
    ...

config:

config['downloads'] = 'Q:/web2py_src/web2py/applications/internet2letter/private/testing/selenium/downloads'
config['handlers'] = 'application/pdf'