immutable_class.py

sample.py

import collections

class Immutable (
  collections.namedtuple('Immutable', [
    'var1',
    'var2',
    'var3',
  ])
):
  # Avoid using dict to store fields as namedtuple docs
  slots = ()
  
  @property
  def sum(self):
    return self.var1 + self.var2