code: @Override
      public GetUICustomizationResult getUICustomization(GetUICustomizationRequest request) {
          request = beforeClientExecution(request);
          return executeGetUICustomization(request);
      }
docs: <p>
  Gets the UI Customization information for a particular app client's app UI, if there is something set. If nothing
  is set for the particular client, but there is an existing pool level customization (app <code>clientId</code>
  will be <code>ALL</code>), then that is returned. If nothing is present, then an empty shape is returned.
  </p>
  
  @param getUICustomizationRequest
  @return Result of the GetUICustomization operation returned by the service.
  @throws InvalidParameterException
  This exception is thrown when the Amazon Cognito service encounters an invalid parameter.
  @throws ResourceNotFoundException
  This exception is thrown when the Amazon Cognito service cannot find the requested resource.
  @throws NotAuthorizedException
  This exception is thrown when a user is not authorized.
  @throws TooManyRequestsException
  This exception is thrown when the user has made too many requests for a given operation.
  @throws InternalErrorException
  This exception is thrown when Amazon Cognito encounters an internal error.
  @sample AWSCognitoIdentityProvider.GetUICustomization
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/cognito-idp-2016-04-18/GetUICustomization" target="_top">AWS
  API Documentation</a>