[Task]: Improving Beam Python Typehints

### What needs to happen?

Can we make Beam Python Typehints better for Beam 3.0? We should scope the work and then make a good plan to land it for Beam 3.0

### Issue Priority

Priority: 2 (default / most normal work should be filed as P2)

### Issue Components

- [x] Component: Python SDK
- [ ] Component: Java SDK
- [ ] Component: Go SDK
- [ ] Component: Typescript SDK
- [ ] Component: IO connector
- [ ] Component: Beam YAML
- [ ] Component: Beam examples
- [ ] Component: Beam playground
- [ ] Component: Beam katas
- [ ] Component: Website
- [ ] Component: Infrastructure
- [ ] Component: Spark Runner
- [ ] Component: Flink Runner
- [ ] Component: Samza Runner
- [ ] Component: Twister2 Runner
- [ ] Component: Hazelcast Jet Runner
- [ ] Component: Google Cloud Dataflow Runner