examples/lists/list_of_lists.py
from __future__ import print_function

x = ['abc', 'def']
print(x)     # ['abc', 'def']

y = [x, 'xyz']
print(y)          # [['abc', 'def'], 'xyz']
print(y[0])       #  ['abc', 'def']
print(y[0][0])    #    abc
print(y[0][0][0]) #    a


z = x + ['qqrq']
print(z)          # ['abc', 'def', 'qqrq']