def detect_indentation(self) -> int:
        """Auto-detect indentation of code.

        Returns:
            int: Number of spaces used to indent code.
        """

        _indentations = {
            len(match.group(1))
            for match in re.finditer(r"^( *)(.*)$", self.plain, flags=re.MULTILINE)
        }

        try:
            indentation = (
                reduce(gcd, [indent for indent in _indentations if not indent % 2]) or 1
            )
        except TypeError:
            indentation = 1

        return indentation
Auto-detect indentation of code.

        Returns:
            int: Number of spaces used to indent code.
        
rich/text.py