new_contents: #!/usr/bin/env python
  # -*- coding: utf-8 -*-
  
  __author__ = 'Yue-Wen FANG'
  __maintainer__ = "Yue-Wen FANG"
  __email__ = 'fyuewen@gmail.com'
  __license__ = 'Apache License 2.0'
  __creation_date__= 'Dec. 26, 2018'
  
  """
  In a CLASS, we do not always need pass external arguments,
  we can also set the default in the class
  """
  
  class Person:
      def __init__(self, name, height='175', weight='200', email='f@jp'):
          """this is an initial"""
          self.name = name
          self.height = height
          self.weight = weight
          self.email = email
          print(self)
          print(type(self))
  
  fang_san = Person('Fang')  # The first instance in this script
  yang_san = Person('Yang', height='150', weight='110', email='hello@jp')  # The second instance here
  
  print('fang_san.email is %s and yang_san.email is %s' % (fang_san.email, yang_san.email))
  
  print('fang_san.weight is %s' % (fang_san.weight))
  
  
subject: use the default arguments in a class