def align_on_left(txt: str) -> str:
    """
    Remove all leading/trailing spaces for each line.
    """
    txt_out = []
    for curr_line in txt.split("\n"):
        curr_line = curr_line.rstrip(" ").lstrip(" ")
        txt_out.append(curr_line)
    res = "\n".join(txt_out)
    return res