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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 set_error_page(self, loadbalancer, html):
 """ A single custom error page may be added per account load balancer with an HTTP protocol. Page updates will override existing content. If a custom error page is deleted, or the load balancer is changed to a non-HTTP protocol, the default error page will be restored. """

        uri = "/loadbalancers/%s/errorpage" % utils.get_id(loadbalancer)
        req_body = {"errorpage": {"content": html}}
        resp, body = self.api.method_put(uri, body=req_body)
        return body