human
I am working on the file "03_advanced/advanced_python_tricks.ipynb".
The first task is:
Instances
Classes can be used to create objects with certain attributes and behavior:
Can you write Python program for it?

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Write me a the Python program you requested?
assistant
#Here is the Python program you requested.

class Dog:
    color = "yellow"
    def __init__(self, name, size):
        self.name = name
        self.size = size
    def bark(self):
        print('whoof, whoof!')

b = Dog("blitzer", 100)
b.bark()