:param str prefix:
    :param str s:
    :return: s with prefix indent added to all lines
    :rtype: str

def add_indent_lines(prefix, s):
    """
    :param str prefix:
    :param str s:
    :return: s with prefix indent added to all lines
    :rtype: str
    """
    if not s:
        return prefix
    prefix_len = str_visible_len(prefix)
    lines = s.splitlines(True)
    return "".join([prefix + lines[0]] + [" " * prefix_len + l for l in lines[1:]])