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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 elevated_permissions(self, permissions, redirect_uri=None):
 """Requests elevated permissions for a set of calendars. :param tuple permissions - calendar permission dicts set each dict must contain values for both `calendar_id` and `permission_level` :param string redirect_uri - A uri to redirect the end user back to after they have either granted or rejected the request for elevated permission. In the case of normal accounts: After making this call the end user will have to grant the extended permissions to their calendar via rhe url returned from the response. In the case of service accounts: After making this call the exteneded permissions will be granted provided the relevant scope has been granted to the account :return: a extended permissions response. :rtype: ``dict`` """


        body = {'permissions': permissions}

        if redirect_uri:
            body['redirect_uri'] = redirect_uri

        return self.request_handler.post('permissions', data=body).json()['permissions_request']