setattr() to add or update value of an attribute of an object in Python

setattr(object, attribute,value) adds or updates the value of attribute of the input object
object (required ) , input object for which the attribute will be updated or added.
attribute ( required ), attribute to be updated / added.
value ( required ), new value of the attribute.

Read more on Class Object and Attributes
Adding new attribute

class Animal():

     #class attributes
    species='carnivores'

     #instance attributes
    def __init__(self1,name1,age):
        self1.name= name1
        self1.age=age

#instantiate the Animal  class
tiger=Animal("Ronald",5)      # object created
setattr(tiger,'height',3.5)   # new attribute added
print(tiger.height)           # showing value of new attribute

Output

3.5

In above code we created an object tiger. By using setattr() we added one more attibute height. The last line will print the value of new attribute.

Updating value of the attribute

We will change the value of one attribute.

class Animal():

     #class attributes
    species='carnivores'

     #instance attributes
    def __init__(self1,name1,age):
        self1.name= name1
        self1.age=age
        

 #instantiate the Animal  class
tiger=Animal("Ronald",5) 
setattr(tiger,'age',6)
print("New age : ",tiger.age)

Output

New age :  6

Setting the value to None

tiger=Animal("Ronald",5) 
setattr(tiger,'age',None)
print("New age : ",tiger.age)

Output

New age :  None

All Built in Functions in Python delattr() getattr() hasattr()

All string methods tuple Python- Tutorials

Subhendu Mohapatra

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