I am getting the following Notice while i install high_contrast module for color change

    Notice: Undefined index: high_contrast in high_contrast_page_attachments() (line 40 of /home/www/html/drupalnew/sites/all/modules/contrib/high_contrast/high_contrast.module)  #0 /home/www/html/drupalnew/core/includes/bootstrap.inc(566): _drupal_error_handler_real(8, 'Undefined index...', '/home/www/html/...', 40, Array)  #1 /home/www/html/drupalnew/sites/all/modules/contrib/high_contrast/high_contrast.module(40): _drupal_error_handler(8, 'Undefined index...', '/home/www/html/...', 40, Array)  #2 /home/www/html/drupalnew/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(297): high_contrast_page_attachments(Array)  #3 /home/www/html/drupalnew/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(273): Drupal\Core\Render\MainContent\HtmlRenderer->invokePageAttachmentHooks(Array)  #4 .... and so on   

Thanks