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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 get_tunnel_ad_url(self):
        ''' Get tunnel hostname from psiturk.org  '''
        req = requests.get('https://api.psiturk.org/api/tunnel',
                           auth=(self.access_key, self.secret_key))
        if req.status_code in [401, 403, 500]:
            print(req.content)
            return False
        else:
            return req.json()['tunnel_hostname']