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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 authentication_url(self):
 """Redirect your users to here to authenticate them."""

        params = {
            'client_id': self.client_id,
            'response_type': self.type,
            'redirect_uri': self.callback_url
        }
        return AUTHENTICATION_URL + "?" + urlencode(params)