def read_python_source(filename: str) -> bytes:
    """Read the Python source text from `filename`.

    Returns bytes.

    """
    with open(filename, "rb") as f:
        source = f.read()

    return source.replace(b"\r\n", b"\n").replace(b"\r", b"\n")
Read the Python source text from `filename`.

    Returns bytes.

    
coverage/python.py