making a first program in ros python code example

Example: how to make a python node

class Node:
  def __init__(self, value, link_node=None):
    self.value = value
    self.link_node = link_node
    
  def set_link_node(self, link_node):
    self.link_node = link_node
    
  def get_link_node(self):
    return self.link_node
  
  def get_value(self):
    return self.value