Please see How do I format code in my posts? for posting code to the forums (or consider some form of online code hosting) as it can be very difficult to interpret Python code without indentation.
You should have a look at the contents of your line_data name when you use .send to provide an additional guest (perhaps print or similar could help). It seems very likely to be in a different format to what you expect.
As an aside it might be worth reviewing any lessons on .send. You should be careful about advancing iteration when .send is used as you have the potential to skip/miss elements from the original generator if you’re not careful, some control flow to avoid such an issue may be useful. Double-check your input/output to make sure your generator actually yields everything that you want it to.