What criteria allow classifying a developer as middle level?

A middle-level developer typically possesses the following criteria:

• Confident proficiency in a programming language (in this case, Python), including the standard library.
• Understanding of basic OOP principles and design patterns.
• Ability to independently develop and maintain moderately complex modules.
• Experience with version control systems and writing tests (unit tests).
• Ability to read and understand others' code, as well as conduct code reviews.
• Knowledge of working with databases, networks, and asynchronous programming (depending on the tasks).
• Ability to estimate task timelines and plan their work.
• Skills in debugging and optimizing code.

A middle developer no longer requires constant supervision and can solve tasks with minimal help from senior colleagues.