list_1 = ['w','h']
list_1.append('y')        # you need no veribal to store list_1.append('y')
print(list_1)             # ['w','h','y']

list_2 = ['a','r','e']
list_1.append(list_2)     # This also donot need a veribal to store it
print(list_1)             # ['w','h','y',['a','r','e']]

list_1.extend(list_2)
print(list_1)             # ['w','h','y',['a','r','e'],'a','r','e']