append a list to another list as element

my_list = ['geeks', 'for'] 
my_list.append('geeks') 
print my_list 

a = ['Jon', 'janni', 'Jannardhan']
b = ['28', '29', '30']
a.append(b)
print(a)
a.pop()
a.extend(b)
print(a)

a = [1, 2, 3]
b = [4, 5, 6]
a += b
# another way: a.extend(b)

list1 = [1,2,3,4,5]
list1.append([6,7])
# ouput = 1,2,3,4,5,6,7