Google doc view test

Fatal error: Uncaught Error: Call to undefined function parabola_posted_on() in /home2/worldlit/public_html/wp-content/themes/parabola-child/single.php:22 Stack trace: #0 /home2/worldlit/public_html/wp-includes/template-loader.php(106): include() #1 /home2/worldlit/public_html/wp-blog-header.php(19): require_once('/home2/worldlit...') #2 /home2/worldlit/public_html/index.php(17): require('/home2/worldlit...') #3 {main} thrown in /home2/worldlit/public_html/wp-content/themes/parabola-child/single.php on line 22