That is to replace all digits, special characters, non-printing characters. I can't use the `re` library.

```
line = line.rstrip() # this get rids of the white spaces
if character in string.digits or character in string.punctuation:
    line = line.replace(character, "")

```

However, this does not get rid of `\`; how can I check for this and replace it with nothing? `character in "\"` does not work.