The Python setattr function serves the purpose of assigning a value to an attribute of an object. This function requires three parameters: the object itself, a string representing the name of the attribute, and an arbitrary value to be assigned. It does not return any value (returns None). This function is particularly useful for adding a new attribute to an object and initializing it with a specified value. Below is the signature of the function.
Python setattr Function Syntax
It has the following syntax:
setattr (object, name, value)
Parameters
- object : It is an object which allows its attributes to be changed.
- name : A name of the attribute.
- value : A value, set to the attribute.
All the parameters are required.
Return
It returns None to the caller function.
Different Examples for Python setattr Function
Let's explore a few instances of the setattr function to grasp its capabilities.
Python setattr Function Example 1
In this section, we are introducing a new attribute and assigning a value to it through the utilization of the setattr function.
class Student:
id = 0
name = ""
def __init__(self, id, name):
self.id = id
self.name = name
student = Student(102,"Sohan")
print(student.id)
print(student.name)
#print(student.email) product error
setattr(student, 'email','[email protected]') # adding new attribute
print(student.email)
Output:
102
Sohan[email protected]
Python setattr Function Example 2
In situations where we prefer not to assign any specific value, we can, by default, utilize None.
class Student:
id = 0
name = ""
def __init__(self, id, name):
self.id = id
self.name = name
student = Student(102,"Sohan")
print(student.id)
print(student.name)
setattr(student, 'email',None) # adding new attribute having None
print(student.email)
Output:
102
Sohan
None
Python setattr Function Example 3
It is possible to reassign (or reset) the value of an attribute even after utilizing the setattr function. Consider the example provided below.
class Student:
id = 0
name = ""
def __init__(self, id, name):
self.id = id
self.name = name
student = Student(102,"Sohan")
print(student.id)
print(student.name)
setattr(student, 'email',None) # adding new attribute having None
student.email = "[email protected]" # Assigning new value
print(student.email)
Output:
102
Sohan[email protected]
