Question

How to define constructor and destructor in Python?

Answer 1

Constructor:

• The constructor is the special function that is automatically executed when an object of a class is created.
• In Python, there is a special function called “init” which acts as a Constructor.
• It must begin and end with a double underscore.
• This function will act as an ordinary function; but the only difference is, it is executed automatically when the object is created.
• This constructor function can be defined with or without arguments. This method is used to initialize the class variables.

Syntax:
_init_ method (Constructor function)
def _init_(self, [args …. ]):
< statements >

Example:

class Sample:
def _init_(self, num):
print(” Constructor of class Sample…”)
self.num=num
print(“The value is :”, num)
S=Sample(10)

Destructor:

• Destructor is also a special method that gets executed automatically when an object exit
• from the scope.
• It is just opposite to the constructor.
• In Python, the _del_ () method is used as the destructor.

Example:

class Example:
def _init_ (self):
print “Object created”
# destructor
def _del_ (self):
print “Object destroyed”
# creating an object
myObj = Example ()

Output:
Object created
Object destroyed