+ if char == '?' or ord(char) < 32 or ord(char) == 127:
+ return ''
+ elif char == '"':
+ return '' if restricted else '\''
+ elif char == ':':
+ return '_-' if restricted else ' -'
+ elif char in '\\/|*<>':
+ return '_'
+ if restricted and (char in '&\'' or char.isspace()):
+ return '_'
+ if restricted and ord(char) > 127: