Python dataclass models

[samwelkanda]

Python dataclasses are a classes that are designed to only hold data values. We should convert existing models from simple classes to dataclasses.

Benefits:

1. Dataclasses are way more readable and maintainable as it removes the need for boilerplate code setters and getters for every property. This removes ~14 lines of code per property.
2. Inbuilt str and repr methods for more helpful representation of data models.
3. Doesn't break existing functionality. Works well with our current setup of serialization/deserialization.
4. We can add convenience methods for serializing and deserializing data models to and from different formats, such as python dictionaries and json with to_dict(), to_json() methods respectively. This can make it much easier for end users to work with their data in different contexts and environments.