class Foo:
  attr = "Common"
  
  def __init__(self, arg1, arg2):
    self.attr1 = arg1
    self.attr2 = arg2

  def use_me(self):
    print("Foo: use_me")

class Bar(Foo):
  def something_new(self):
    print("Bar: something_new")

class XYZ:
  def xyz(self):
    print("XYZ: xyz")

class Strange(Bar, XYZ): # Multiple inheritance
  pass


def main():
  f = Foo(1, 3)
  b = Bar(1, 3)
  xyz = XYZ()
  s = Strange(1, 3)
  
  b.something_new() # Bar: something_new
  b.use_me()        # Foo: use_me
  
  s.something_new() # Bar: something_new
  s.use_me()        # Foo: use_me
  s.xyz()           # XYZ: xyz

if __name__ == '__main__':
  main()