from typing import Tuple


def cut_at_line(text: str, marker: str) -> Tuple[str, str]:
    """
    Split text into two parts: up to the line with marker, and lines after.

    If `marker` isn't in the text, return ("", text)
    """
    lines = text.splitlines(keepends=True)
    for i, line in enumerate(lines):
        if marker in line:
            return "".join(lines[: i + 1]), "".join(lines[i + 1 :])
    return ("", text)