Attributes

Understanding Attributes#

In Python, when we say “attribute”, we refer to any name following a dot after an instance of a class. For example, when we say object.attribute, ‘attribute’ is an attribute of the class instance ‘object’. They hold data pertaining to an instance and define the characteristics of an object.

Declaring Attributes#

Attributes are typically declared within the class definition. However, they can also be dynamically added to an instance after the instance has been created. Check the code below:

 1class Robot:
 2    def __init__(self, name, color):
 3        self.name = name            # adding attribute 'name'
 4        self.color = color          # adding attribute 'color'
 5
 6r1 = Robot('Beepo', 'yellow')
 7
 8# Dynamically adding attribute 'height'
 9r1.height = 16
10print(r1.height)   # Output: 16

Accessing Attributes#

Attributes can be accessed using the dot operator on an instance of the class.

1r2 = Robot('Rob', 'red')
2print(r2.name)   # Output: Rob
3print(r2.color)  # Output: red

Modifying Attributes#

Similar to accessing, modifying an attribute can be done using the dot operator.

1r3 = Robot('Spark', 'blue')
2print(r3.name)   # Output: Spark
3
4r3.name = 'Bolt'
5print(r3.name)   # Output: Bolt

Here, we initially declared the robot’s name as ‘Spark’ and then changed it to ‘Bolt’.