def METHOD_NAME(self, *args):
    """\
    Helper function to read a single line from a file.
    One or more parameters are allowed, they are joined with os.path.join.
    Returns None on errors..
    """
    try:
        with open(os.path.join(*args)) as f:
            line = f.readline().strip()
        return line
    except IOError:
        return None