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Hello world in Java: understanding against python concept

I'm trying to learn Java now, and this is a welcome global program, and it has already begun to disorient me. I'm used to python, and I found this tutorial (ebook) simple and concise for programmers who have a python background.

Hi, a mundane Java program from a book:

public class Hello {

public static void main (String[] args) {

     System.out.println("Hello World!");
}
}

As the book says, the equivalent code for this in python is:

class Hello(object):
  @staticmethod
  def main(args):
     print "Hello World!"

I fully understand the python code. However, I have a problem with Java code, and I want to be clear before proceeding to get a basic knowledge of the language in my brain.

The book says (as copied from the book):

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