Python hasattr() Built in Function

Python hasattr() is a built-in function that returns True if an object has a given attribute, otherwise False. An attribute can be a variable, a method, a property, etc. that belongs to an object.

Here are some examples of how to use Python hasattr():

To check if an object has an attribute defined in its class:

class Car:
    brand = "Ford"
    number = 7786

car = Car()
print(hasattr(car, "brand")) # returns True
print(hasattr(car, "color")) # returns False

To check if an object has an attribute defined dynamically:

class Person:
    name = "John"
    age = 36

person = Person()
person.country = "Norway" # defines a new attribute dynamically
print(hasattr(person, "country")) # returns True

To check if an object has a method or a property:

class Circle:
    def __init__(self, radius):
        self.radius = radius

    def area(self): # defines a method
        return 3.14 * self.radius ** 2

    @property
    def diameter(self): # defines a property
        return 2 * self.radius

circle = Circle(5)
print(hasattr(circle, "area")) # returns True
print(hasattr(circle, "diameter")) # returns True

If you have any questions about this code, you can drop a line in comment.

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