Question

Why are constructors indeed called "Constructors"? What is their purpose and how are they different from methods in a class?

Also, can there be more that one __init__ in a class? I tried the following, can someone please explain the result?

>>> class test:
    def __init__(self):
        print "init 1"
    def __init__(self):
        print "init 2"

>>> s=test()
init 2

Finally, is __init__ an operator overloader?

Answer 1

There is no function overloading in Python, meaning that you can’t have multiple functions with the same name but different arguments.

In your code example, you’re not overloading __init__(). What happens is that the second definition rebinds the name __init__ to the new method, rendering the first method inaccessible.

As to your general question about constructors, Wikipedia is a good starting point. For Python-specific stuff, I highly recommend the Python docs.