Why is the function not working in the class?

Question

Python

Why it works:

def clean(text: str):
    return text \
        .replace('?', '') \
        .replace("|", '') \
        .replace('\"', '') \
        .replace('  ', '') \
        .replace(':', '') \
        .replace('\\', '') \
        .replace('/', '') \
        .replace('>', '') \
        .replace('<', '') \
        .replace('"', '') \
        .replace('+', '') \
        .replace('*', '') \
        .replace(' .', '')
...

class ParseText:

...

    def save_text(self):
        part = open('src/text/{}.txt'.format(clean(partName)), 'w', encoding="utf-8")

And this doesn't work:

def clean(text: str):
    strings = ['?', "|", '\"', ]
    result = (text.replace(i, "") for i in strings)
    result = str()
    for i in strings:
        print(i)
        result = text.replace(i, '')
        continue
    return result
...

class ParseText:

...

    def save_text(self):
        part = open('src/text/{}.txt'.format(clean(partName)), 'w', encoding="utf-8")

Answer 1

Because strings are immutable, the replace method cannot change the original string (like any other method) and it returns a new string with everything replaced. In the first case, each subsequent call acts on the string returned by the previous one and eventually returns the correct result.
And it’s also unnecessary to write continue at the end of the loop, it will go on anyway. And set the variable to zero using constructions = str()
Example:

In [4]: a = "abc"

In [5]: b = a.replace("a", "1")

In [6]: print(a,b)
abc 1bc