Assign and print Long Variable in python

I am new to python.And one of my requirement is to deal with long values.The problem is i didnt know how to assign a long value.This question might be very silly.But im just now starting to learn the language.I have seen a blog and i tried something like this :

# Long program in Python
x=1
y = long(x)
print(type(y))

But i am getting an error like this:

Traceback (most recent call last):                                
File "main.py", line 4, in <module>                             
y = long(x)                                                   
NameError: name 'long' is not defined 

Can anyone please help me in acheiving this?