Write a number class MyNum with a number constructor, += operator, and a get_val() method that returns a value.

class MyNum(object):
  def __init__(self, num):
    self.num = num
    
  def get_val(self):
    return self.num
    
  def __iadd__(self, val):
    self.num += val
    return self
    
a = MyNum(2)
a += 3
# a.get_val()
a.get_val()