import re


def _dos2unix(file_content: bytes) -> bytes:
    """
    Replace occurrences of Windows line terminator CR/LF with only LF.

    :param file_content: the content of the file.
    :return: the same content but with the line terminator
    """
    return re.sub(b"\r\n", b"\n", file_content, flags=re.M)