Now, we have a basic class, but it's fairly useless. It doesn't contain any data, and it doesn't do anything. What do we have to do to assign an attribute to a given object?
In fact, we don't have to do anything special in the class definition. We can set arbitrary attributes on an instantiated object using dot notation:
class Point:
pass
p1 = Point()
p2 = Point()
p1.x = 5
p1.y = 4
p2.x = 3
p2.y = 6
print(p1.x, p1.y)
print(p2.x, p2.y)
If we run this code, the two print statements at the end tell us the new attribute values on the two objects:
5 4 3 6
This code creates an empty Point class with no data or behaviors. Then, it creates two instances of that class and assigns each of those instances x and y coordinates to identify a point in two dimensions. All we need to do to assign a value to an attribute on an object is use the <object>.<attribute> = <value> syntax. This is sometimes referred to as dot notation. You have likely encountered this same notation before when reading attributes on objects provided by the standard library or a third-party library. The value can be anything: a Python primitive, a built-in data type, or another object. It can even be a function or another class!