code: @Override
      public GetGroupCertificateAuthorityResult getGroupCertificateAuthority(GetGroupCertificateAuthorityRequest request) {
          request = beforeClientExecution(request);
          return executeGetGroupCertificateAuthority(request);
      }
docs: Retreives the CA associated with a group. Returns the public key of the CA.
  
  @param getGroupCertificateAuthorityRequest
  @return Result of the GetGroupCertificateAuthority operation returned by the service.
  @throws BadRequestException
  invalid request
  @throws InternalServerErrorException
  server error
  @sample AWSGreengrass.GetGroupCertificateAuthority
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/greengrass-2017-06-07/GetGroupCertificateAuthority"
  target="_top">AWS API Documentation</a>