code: def importSignedCertificate(self, alias, certFile):
          
          params = { "f" : "json" }
          files = {"file" : certFile}
          url = self._url + \
              "/sslCertificates/{cert}/importSignedCertificate".format(cert=alias)
          return self._post(url=url,
                            files=files,
                            param_dict=params,
                            proxy_port=self._proxy_port,
                            proxy_url=self._proxy_url)
docs: This operation imports a certificate authority (CA) signed SSL
          certificate into the key store.