Update app.py

app.py

@@ -52,7 +52,7 @@ def promptgen(choice, num, artist):
   vocab = len(prompt)
   generated = []
   artists_num = 0
-  with open('gen_prompt.txt', 'wb') as f:
+  with open('gen_prompt.txt', 'w') as f:
       while len(sorted(set(generated), key=lambda d: generated.index(d))) < num:
         rand = random.randint(0, vocab)
         if prompt[rand-1].startswith('art by') and artists_num < artist: