How to count number of instances of a class in Python?

Instances of a class mean the objects created for a particular class. A single class can have multiple objects of it. Here, we will find the count of the number of instances of a class in Python.

Approach:

• Whenever an object is created, the constructor of that particular class is called.
• Constructor is a function whose name is the same as that of class name and it doesn’t have any return type. A constructor is used to initialize the variables of a class.
• Whenever a constructor is called which means a new object is created, we just have to increment a counter that will keep track of the no. of objects that particular class has.
  

Below is the implementation:

Python3

# code
class geeks:

    # this is used to print the number
    # of instances of a class
    counter = 0

    # constructor of geeks class
    def __init__(self):

        # increment
        geeks.counter += 1


# object or instance of geeks class
g1 = geeks()
g2 = geeks()
g3 = geeks()
print(geeks.counter)

Output:

3