def indent(text: str) -> str:
    """
    Indent each line in a string.
    """
    lines = text.replace("\r", "").split("\n")
    new_lines = []
    for line in lines:
        if len(line.strip()) == 0:
            new_lines.append("")
        else:
            new_lines.append("\t" + line)
    return "\n".join(new_lines)