Flash cards
Review the key moves
What is the main idea behind Python init() Method?
Lesson checks
Practice each idea before moving on
Short Mimo-style checks built from this lesson's code, terms, and sequence.
Which statement best captures the main point of this lesson?
Put the learning moves in the order that makes the concept easiest to apply.
The __init__() Method
All classes have a built-in method called init() , which is always executed when the class is being initiated.
The init() method is used to assign values to object properties, or to perform operations that are necessary when the object is being created.
__init__()Note
The init() method is called automatically every time the class is being used to create a new object.
Why Use __init__()?
Without the init() method, you would need to set properties manually for each object:
__init__()Using init() makes it easier to create objects with initial values:
__init__()Default Values in __init__()
You can also set default values for parameters in the init() method:
Example
class Person:
def __init__(self, name, age=18):
self.name = name
self.age = age
p1 = Person("Emil")
p2 = Person("Tobias", 25)
print(p1.name, p1.age)
print(p2.name, p2.age)Multiple Parameters
The init() method can have as many parameters as you need:
Example
class Person:
def __init__(self, name, age, city, country):
self.name = name
self.age = age
self.city = city
self.country = country
p1 = Person("Linus", 30, "Oslo", "Norway")
print(p1.name)
print(p1.age)
print(p1.city)
print(p1.country)