def METHOD_NAME(filename):
    """
    Reads a whole binary file in and returns bytes(). If the file to be read is called '-'
    then an empty bytes is returned.
    """
    if filename == "-":
        return bytes([])
    try:
        with open(filename, "rb") as input_fd:
            contents = input_fd.read()
        return contents
    except:
        print('File "%s" is not a readable file' % (filename))
        return None