Check to ensure appends are strings

scrape.py

@@ -182,12 +182,14 @@ class Webdriver:
 def append_upcoming_and_img_urls(source):
   soup = BeautifulSoup(source, 'html.parser')
   for link in soup.find_all('a'):
+    if type(link.get('href')) == str:
       if link.get('href') not in visited_urls and link.get('href') not in banned_urls and link.get('href') not in upcoming_urls:
         if link.get('href').startswith('GUID') and link.get('href').endswith('.html'):
           upcoming_urls.append(link.get('href'))
 
   for img in soup.find_all('img'):
     if img.get('src') not in img_urls:
+      if type(img.get('src')) == str:
         img_urls.append(img.get('src'))
 
 def check_source_validity(source):