def star_import_usage_undefined_name(messages):
    """Yield line number, undefined name, and its possible origin module."""
    for message in messages:
        if isinstance(message, pyflakes.messages.ImportStarUsage):
            undefined_name = message.message_args[0]
            module_name = message.message_args[1]
            yield (message.lineno, undefined_name, module_name)
Yield line number, undefined name, and its possible origin module.