O código abaixo está retornando erros que não consigo corrigir. Alguém pode ajudar?

import random
from urllib.request import urlopen
import sys

WORD_URL = 'http://learncodethehardway.org/words.txt'
WORDS = []

PHRASES = {"class %%%(%%%):":"Make a class named %%% that is-a %%%",
           "class %%%(object):\n\tdef __init__(self, ***)" :
           "class %%% has-a __init__ that takes self and *** params.",
           "class %%% (object):\n\tdef ***(self,@@@)":
           "class %%% has-a function *** that takes self and @@@ params.",
           "*** = %%%()":
           "Set *** to an instance of class %%%.",
           "***.*** = '***'":
           "From *** get the *** attribute and set i to '%%%'."
           }

if len(sys.argv) == 2 and sys.argv[i] == "english":
    PHRASES_FIRST = True
else:
    PHRASES_FIRST = False

for word in urlopen(WORD_URL).readlines():
    WORDS.append(str(word.strip(), encoding='utf-8'))

def convert(snippet, phrase):
    class_names = [w.capitalize() for w in
        random.sample(WORDS,snippet.count("%%%"))]
    other_names = random.sample(WORDS, snippet.count("%%%"))
    results = []
    param_names = []

    for i in range(0, snippet.count("@@@")):
        param_count = random.randint(1,3)
        param_names.append(','.join(
        random.sample(WORDS, param_count)))

    for word in class_names:
        result = result.replace("%%%", word, 1)

    for word in other_names:
        result = result.replace("%%%", word, 1)

    for word in param_names:
        result = result.replace("@@@", word, 1)

    results.append(result)

    return results

try:
    while True:
        snippets = list(PHRASES.keys())
        random.shuffle(snippets)

        for snippet in snippets:
            phrase = PHRASES[snippet]
            question, answer = convert(snippet, phrase)
            if PHRASES_FIRST:
                question, answer = answer, question

            print(question)

            input("> ")
            print(f"ANSWER: {answer}\n\n")
except EOFError:
    print("\nBye")