class Demo:
    def __init__(self):
        pass
 
    def test(self):
        print(__name__)
 
obj = Demo()
obj.test()

>>> class demo():
	def __repr__(self):
		return '__repr__ built-in function called'
	def __str__(self):
		return '__str__ built-in function called'
>>> s=demo()
>>> s

>>> class demo():
	def __repr__(self):
		return '__repr__ built-in function called'
	def __str__(self):
		return '__str__  built-in function called'
>>> s=demo()
>>> print(s)

class stud:
   def __init__(self, roll_no, grade):
      self.roll_no = roll_no
      self.grade = grade
   def display (self):
      print("Roll no : ", self.roll_no,  ", Grade: ", self.grade)
stud1 = stud(34, ‘S’)
stud1.age=7
print(hasattr(stud1, 'age'))

class stud:
   ‘Base class for all students’
   def __init__(self, roll_no, grade):
      self.roll_no = roll_no
      self.grade = grade
   def display (self):
      print("Roll no : ", self.roll_no,  ", Grade: ", self.grade)
print(student.__doc__)