Undefined variable: note in woo-donations.php

This line of code in the file woo-donations.php is giving a notice of undefined variable. The notice says
Notice: Undefined variable: note in woo-donations.php on line 119

	
if(!empty($product) && $note=='on'){
		$note_html = '<textarea id="w3mission" rows="3" cols="20" placeholder="Note" name="donation_note" class="donation_note"></textarea>';
	}

Help is appreciated