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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 authorization_url(self, response, state=""):
 """ Return the authorization url that's needed to authorize as a user. :param response: Can be either code or pin. If it's code the user will be redirected to your redirect url with the code as a get parameter after authorizing your application. If it's pin then after authorizing your application, the user will instead be shown a pin on Imgurs website. Both code and pin are used to get an access_token and refresh token with the exchange_code and exchange_pin functions respectively. :param state: This optional parameter indicates any state which may be useful to your application upon receipt of the response. Imgur round-trips this parameter, so your application receives the same value it sent. Possible uses include redirecting the user to the correct resource in your site, nonces, and cross-site-request-forgery mitigations. """

        return AUTHORIZE_URL.format(self._base_url, self.client_id, response, state)