In this tutorial, we will learn Python Destructors

In Python, destructors are special methods that are automatically invoked when an object is about to be destroyed or garbage collected. They are defined using the __del__ method in a class. The destructor is useful for releasing resources, such as closing files or database connections, before an object is destroyed.

Here’s an example that demonstrates the usage of a destructor:

class MyClass:
    def __init__(self):
        print("Constructor called.")

    def __del__(self):
        print("Destructor called.")

# Create an instance of MyClass
obj = MyClass()

# The instance is no longer needed
del obj

In this example, when you create an instance of MyClass using obj = MyClass(), the constructor __init__ is called and it prints “Constructor called.”. Later, when you delete the obj using del obj, Python invokes the destructor __del__ before destroying the object, and it prints “Destructor called.”.

The __del__ method is automatically invoked when there are no more references to an object, and it’s up to the Python interpreter to determine when exactly that happens. Note that the destructor may not be called immediately after the last reference to the object is removed. The timing depends on the garbage collector and the memory management mechanism used by Python.

It’s important to note that the destructor may not be called immediately after the object is no longer referenced. Python uses a garbage collector that runs periodically to determine which objects are no longer needed and frees their memory. The exact timing of when the destructor is called is therefore not guaranteed.

Additionally, it’s generally recommended to rely on explicit cleanup methods (e.g., close()) rather than destructors to release resources. The __del__ method should be used sparingly, and it’s not the preferred approach for managing resources in Python.

It’s worth noting that in some cases, the __del__ method might not be executed at all, especially in scenarios involving circular references. Therefore, it’s important to be cautious when using destructors and to rely on other means for cleanup when possible.