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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_logview_address(self, hours=None):
 """ Get logview address of the instance object by hours. :param hours: :return: logview address :rtype: str """

        hours = hours or options.log_view_hours

        project = self.project
        url = '%s/authorization' % project.resource()

        policy = {
            'expires_in_hours': hours,
            'policy': {
                'Statement': [{
                    'Action': ['odps:Read'],
                    'Effect': 'Allow',
                    'Resource': 'acs:odps:*:projects/%s/instances/%s' % \
                                (project.name, self.id)
                }],
                'Version': '1',
            }
        }
        headers = {'Content-Type': 'application/json'}
        params = {'sign_bearer_token': ''}
        data = json.dumps(policy)
        res = self._client.post(url, data, headers=headers, params=params)

        content = res.text if six.PY3 else res.content
        root = ElementTree.fromstring(content)
        token = root.find('Result').text

        link = options.log_view_host + "/logview/?h=" + self._client.endpoint + "&p=" \
               + project.name + "&i=" + self.id + "&token=" + token
        return link