Instance, Static, Class Methods in Python

Instance Methods in Python

• The most common type of methods in Python classes, instance methods are called as they are because they can and should access unique data of each instance.
• Instanec methods must have self as a parameter
• Of course, instance methods do not require decorators; any method you create will automatically be created as an instance method, unless you specify a method type to Python

Static Methods in Python

• Static methods do not require accessing any class-specific data, though they are still related to a class in some way
• No need for self parameter
• No need to instantiate an instance to use this method; simply call it
• @staticmethod decorator tells Python that this method is a static method
• Great for utility functions that need to perform a task in isolation, that don't and can't access class data; they should only be working with data passed in as arguments

class ExampleClass:

	greeting = ""

	def __init__(self, name):
    		greeting = "Hello " + name  
        
	@staticmethod
	def function_example():
    		print('Tis a static method')

Class Methods in Python

• Class methods cannot access specific instance data, but they do know about thier class -- they can access class variables and other static methods
• Also do not need self parameter, but requires cls parameter
• Class methods use the @classmethod decorator

class ExampleClass:
	greeting = ""

	def __init__(self, name):
    		greeting = "Hello " + name

	@classmethod
	def function_example(cls):
   	 	print("Tis a class method")
		cls.other_static_function()

Referenced article