Final answer:
Python's garbage collection mechanism uses reference counting to track object references and deallocates memory when the count drops to zero. It also includes a cyclic garbage collector to handle circular references within complex data structures.
Step-by-step explanation:
Python's garbage collection mechanism is primarily based on reference counting. This means that every object in Python has a reference count that keeps track of how many references point to it. When an object's reference count drops to zero, because no references point to it anymore, the object is automatically removed from memory by the garbage collector.
Apart from reference counting, Python's garbage collector also includes a cyclic garbage collector that can detect and collect cycles of objects with references to each other that would not be collectable otherwise, as their reference counts never reach zero. This is particularly useful in managing complex data structures where cycles may occur.
The Python garbage collector
The garbage collector is invoked automatically, and developers generally do not need to worry about memory management, although it is possible to manually trigger garbage collection or disable the cyclic garbage collector if needed for certain performance-critical applications.