Removing cycles may require extensive refactoring of the code, sometimes resulting in unintuitive layouts. All, just to solve the cyclic-import errors. At the

Removing cycles may require extensive refactoring of the code, sometimes resulting in unintuitive layouts. All, just to solve the cyclic-import errors. At the core of the problem is the fact that there's no thing as "partial import" in Python. When you do "from M import A" in Python, all the contents of M are evaluated and a reference to A is added to the current namespace. So, cyclic dependencies arise sooner or later, unless you adopt some very un-pythonic style for your codebase (e.g. one file per class).