Python’s magic method
__del__() is called the finalizer method or, wrongly, the destructor method — the latter being wrong because it doesn’t actually destroy the object. Python calls
__del__() upon deletion of a given instance. For example, the expression
del my_obj will eventually initiate
We call this a “Dunder Method” for “Double Underscore Method” (also called “magic method”). To get a list of all dunder methods with explanation, check out our dunder cheat sheet article on this blog.
💡 Note: the expression
del my_obj actually decrements the reference count for
my_obj. It doesn’t directly call
my_obj.__del__()because this method is only called when the reference count reaches zero.
Syntax and Example
Let’s have a look at an example:
class MyClass: def __del__(self): print('hello world') my_obj = MyClass() del my_obj # hello world
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