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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 construct_oauth_url(self):
 """ Constructs verifier OAuth URL """

        response = self._requester(requests.head, 
                                   "{0}://{1}/".format(self.protocol, self.client.server),
                                   allow_redirects=False
                                  )
        if response.is_redirect:
            server = response.headers['location']
        else:
            server = response.url

        path = "oauth/authorize?oauth_token={token}".format(
            token=self.store["oauth-request-token"]
        )
        return "{server}{path}".format(
            server=server,
            path=path
        )