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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 authorize():
 """Authorize to twitter. Use PIN authentification. :returns: Token for authentificate with Twitter. :rtype: :class:`autotweet.twitter.OAuthToken` """

    auth = tweepy.OAuthHandler(CONSUMER_KEY, CONSUMER_SECRET)
    url = auth.get_authorization_url()
    print('Open this url on your webbrowser: {0}'.format(url))
    webbrowser.open(url)
    pin = input('Input verification number here: ').strip()

    token_key, token_secret = auth.get_access_token(verifier=pin)

    return OAuthToken(token_key, token_secret)