How did you familiarize yourself with the principles of SOLID and how did you apply them in practice?

SOLID principles are a set of five fundamental object-oriented programming principles aimed at improving the structure and maintainability of code:

• S (Single Responsibility Principle) — a class should have one responsibility.
• O (Open/Closed Principle) — software entities should be open for extension but closed for modification.
• L (Liskov Substitution Principle) — objects of subclasses should be interchangeable with objects of the base class.
• I (Interface Segregation Principle) — it's better to have many specific interfaces than a single general-purpose one.
• D (Dependency Inversion Principle) — dependencies should be based on abstractions, not on concrete implementations.

In practice, I applied these principles by, for example, separating classes based on their responsibilities to facilitate testing and maintenance. I used abstractions and interfaces to reduce coupling between modules. This helped in writing more flexible and extensible code.

An example of applying SRP in Python:

class ReportGenerator:
    def generate(self):
        # report generation logic
        pass

class ReportSaver:
    def save(self, report):
        # report saving logic
        pass

Here, report generation and saving are separated into different classes, which simplifies maintenance.