# Python program to print all
# sublist from a given list
# function to generate all the sub lists
def sub_lists (l):
lists = [[]]
for i in range(len(l) + 1):
for j in range(i):
lists.append(l[j: i])
return lists
# driver code
l1 = [1, 2, 3]
print(sub_lists(l1))