List of Lists

matrix = [[1, 2, 3],[4, 5, 6],[7, 8, 9]]


#how-to-access
print(matrix)
print(matrix[0])      # [1, 2, 3]
print(matrix[0][1])   # 2
print(matrix[2][2])   # 9


List of Dictionaries 

students = [{"name": "Mohan", "age": 25, "marks": 90},{"name": "Raj", "age": 24, "marks": 85},{"name": "Kumar", "age": 26, "marks": 88}]

#how-to-access
print(students)
print(students[0])           # First dictionary
print(students[0]["name"])  # Mohan
print(students[1]["marks"]) # 85


dictionary of lists

students = {"names": ["Mohan", "Raj", "Kumar"],"marks": [90, 85, 88]}


#how-to-access
print(students)
print(students["names"])      # ['Mohan', 'Raj', 'Kumar']
print(students["names"][0])   # Mohan
print(students["marks"][1])   # 85


Dictionary of dictionaries

 devices = {"router1": {"ip": "10.0.0.1","vendor": "Cisco","status": "up"},"switch1": {"ip": "10.0.0.2","vendor": "Juniper","status": "down"}}


#how-to-access
print(devices["router1"]["ip"])   # 10.0.0.1
print(devices["router2"]["vendor"])   # Juniper