def pos(dot, at):
    """Create a human-readable position of a PFA element in a JSON file."""
    if at is None or at == "":
        return "at {0}".format("" if (dot == "") else "PFA field \"" + dot + "\"")
    else:
        return "at {0}{1}".format(at, "" if (dot == "") else " (PFA field \"" + dot + "\")")