'Return the OAuth URL to request tokens from.
We first check the usual OAuth settings, and then fall back to
https://accounts.google.com/o/oauth2/token if nothing is
specified.'

def getoauth2_request_url(self):

    url = super(GmailRepository, self).getoauth2_request_url()
    if (url is None):
        self.setoauth2_request_url('https://accounts.google.com/o/oauth2/token')
    else:
        self.setoauth2_request_url(url)
    return self.oauth2_request_url
