What is the purpose of the `self` parameter? Why is it needed?
The self
parameter in Python is used to refer to the instance of an object within a class. It is used to access the attributes and methods of that specific instance of the class.
It is needed because when a method is called on an instance of a class, the interpreter needs a way to know which instance of the class the method is being called on. Without the self
parameter, the interpreter would not know which instance of the class to reference, and the method would not be able to access the appropriate attributes or methods.
For example, if a class has an attribute called name
, and a method called print_name()
that prints the value of the name
attribute, the self
parameter is used within the print_name()
method to reference the specific instance of the class, and access its name
attribute:
class MyClass:
def __init__(self, name):
self.name = name
def print_name(self):
print(self.name)
my_instance = MyClass("John")
my_instance.print_name() # prints "John"
Without the self
parameter in the print_name()
method, the interpreter would not know which instance of the class to reference, and the method would not be able to access the name
attribute.