How To Delete A Property From An Object In Python

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Summary: in this tutorial, you’ll learn how to use the property() class to delete the property of an object.

To create a property of a class, you use the @property decorator. Underhood, the @property decorator uses the property class that has three methods: setter, getter, and deleter.

By using the deleter, you can delete a property from an object. Notice that the deleter() method deletes a property of an object, not a class.

The following defines the Person class with the name property:

from pprint import pprint class Person: def __init__(self, name): self._name = name @property def name(self): return self._name @name.setter def name(self, value): if value.strip() == '': raise ValueError('name cannot be empty') self._name = value @name.deleter def name(self): del self._nameCode language: Python (python)

In the Person class, we use the @name.deleter decorator. Inside the deleter, we use the del keyword to delete the _name attribute of the Person instance.

The following shows the __dict__ of the Person class:

pprint(Person.__dict__)Code language: Python (python)

Output:

mappingproxy({'__dict__': <attribute '__dict__' of 'Person' objects>, '__doc__': None, '__init__': <function Person.__init__ at 0x000001DC41D62670>, '__module__': '__main__', '__weakref__': <attribute '__weakref__' of 'Person' objects>, 'name': <property object at 0x000001DC41C89130>})Code language: Python (python)

The Person.__dict__ class has the name variable. The following creates a new instance of the Person class:

person = Person('John')Code language: Python (python)

The person.__dict__ has the _name attribute:

pprint(person.__dict__)Code language: Python (python)

Output:

{'_name': 'John'}Code language: Python (python)

The following uses the del keyword to delete the name property:

del person.nameCode language: Python (python)

Internally, Python will execute the deleter method that deletes the _name attribute from the person object. The person.__dict__ will be empty like this:

{}Code language: Python (python)

And if you attempt to access name property again, you’ll get an error:

print(person.name)Code language: Python (python)

Error:

AttributeError: 'Person' object has no attribute '_name'Code language: Python (python)

Summary #

  • Use the deleter decorator to delete a property of an instance of a class.

Quiz #

<iframe name="quiz" src="/quiz/?quiz=delete-property" height="700" width="600" class="iframe" ></iframe>Code language: HTML, XML (xml)

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