Cannot redeclare has_shortcode WP 3.6.1

Hi there,

I’ve read some topics here about function has_shortcode creating an error once updating to wordpress 3.6.1 ,.. i’ve found the piece of code causing it in functions.php of my theme.
However i need this code so i can’t just comment it out i decide it’s redundant. Can someone tell me how it should be rewritten?

Here it is:

// check the current post for the existence of a short code
function has_shortcode($shortcode = '') {
		$post_to_check = get_post(get_the_ID());
		// false because we have to search through the post content first
		$found = false;
	// if no short code was provided, return false
	if (!$shortcode) {
		return $found;
}
	// check the post content for the short code
	if ( stripos($post_to_check->post_content, '[' . $shortcode) !== false ) {
		// we have found the short code
		$found = true;
	}
	// return our final results
	return $found; }?>

Thanks a lot!