Object-Oriented Programming in Python
You should have gotten the point by now that everything is an object in Python.
Here is a reminder of how to define a class and instantiate a class instance.
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class Person:
pass
person = Person()
print(type(person))
While the general OOP concepts are the same as in Java, there are many specific details in Python where things are implemented differently. Some of these requires a different way of thinking from what you have been exposed to in Java.
Firstly, if all you really need is a class with no methods, then perhaps you should consider using a dict instead of a class?
Otherwise, below is an example class definition in Python, and how to use the class. Copy and paste the code into a text file, save it as person.py, and run it with python3 person.py to check out the output.
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class Person:
def __init__(self, firstname, lastname, age):
self.firstname = firstname
self.lastname = lastname
self.age = age
def greet(self, message):
print(f"{self.firstname} {self.lastname} says {message}!")
def get_fullname(self):
return f"{self.firstname} {self.lastname}"
def __str__(self):
return f"A person named {self.get_fullname()} aged {self.age}"
person = Person("Josiah", "Wang", 20) # What do you mean I don't look 20? :D
person.greet("I love Machine Learning!")
print(person.age)
print(person.get_fullname())
print(person)
print(type(person))
print(isinstance(person, Person))
print(isinstance(person, object))