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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 begin_auth(request):
 """The view function that initiates the entire handshake. For the most part, this is 100% drag and drop. """

    # Instantiate Twython with the first leg of our trip.
    twitter = Twython(settings.TWITTER_KEY, settings.TWITTER_SECRET)

    # Request an authorization url to send the user to...
    callback_url = request.build_absolute_uri(reverse('twython_django_oauth.views.thanks'))
    auth_props = twitter.get_authentication_tokens(callback_url)

    # Then send them over there, durh.
    request.session['request_token'] = auth_props

    request.session['next_url'] = request.GET.get('next',None)
    
    return HttpResponseRedirect(auth_props['auth_url'])