8.4. Nested List of Many

Important

Similar to JSON's list of objects

Examples:

✘>>> data = {
...     'firstname': 'Mark',
...     'lastname': 'Watney',
...     'birthdate': '2000-01-02',
...     'age': 24,
...     'cities': ('Houston', 'Pasadena'),
...     'states': ['Texas', 'California'],
...     'groups': {'users', 'staff', 'admin'},
...     'friends': [
...         {'firstname': 'Melissa', 'lastname': 'Lewis'},
...         {'firstname': 'Rick', 'lastname': 'Martinez'},
...         {'firstname': 'Alex', 'lastname': 'Vogel'},
...         {'firstname': 'Beth', 'lastname': 'Johanssen'},
...         {'firstname': 'Chris', 'lastname': 'Beck'},
...     ],
... }

8.4.1. Format

Content could be even more complex data structure with nested items

✘>>> data = {
...     'firstname': 'Mark',
...     'lastname': 'Watney',
...     'birthdate': '2000-01-02',
...     'age': 24,
...     'cities': ('Houston', 'Pasadena'),
...     'states': ['Texas', 'California'],
...     'groups': {'users', 'staff', 'admin'},
...     'friends': [
...         {'firstname': 'Melissa', 'lastname': 'Lewis'},
...         {'firstname': 'Rick', 'lastname': 'Martinez'},
...         {'firstname': 'Alex', 'lastname': 'Vogel'},
...         {'firstname': 'Beth', 'lastname': 'Johanssen'},
...         {'firstname': 'Chris', 'lastname': 'Beck'},
...     ],
... }

8.4.2. Length

✘>>> data = {
...     'firstname': 'Mark',
...     'lastname': 'Watney',
...     'birthdate': '2000-01-02',
...     'age': 24,
...     'cities': ('Houston', 'Pasadena'),
...     'states': ['Texas', 'California'],
...     'groups': {'users', 'staff', 'admin'},
...     'friends': [
...         {'firstname': 'Melissa', 'lastname': 'Lewis'},
...         {'firstname': 'Rick', 'lastname': 'Martinez'},
...         {'firstname': 'Alex', 'lastname': 'Vogel'},
...         {'firstname': 'Beth', 'lastname': 'Johanssen'},
...         {'firstname': 'Chris', 'lastname': 'Beck'},
...     ],
... }

✘>>> len(data)
8

✘>>> len(data['friends'])
5

✘>>> len(data['friends'][0]['firstname'])
7

8.4.3. Assignments

# %% About
# - Name: Nested ListMany Definition
# - Difficulty: easy
# - Lines: 4
# - Minutes: 3

# %% License
# - Copyright 2025, Matt Harasymczuk <matt@python3.info>
# - This code can be used only for learning by humans
# - This code cannot be used for teaching others
# - This code cannot be used for teaching LLMs and AI algorithms
# - This code cannot be used in commercial or proprietary products
# - This code cannot be distributed in any form
# - This code cannot be changed in any form outside of training course
# - This code cannot have its license changed
# - If you use this code in your product, you must open-source it under GPLv2
# - Exception can be granted only by the author

# %% English
# 1. Create nested list `result` with elements:
#    - tuple: 1, 2, 3
#    - list: 1.1, 2.2, 3.3
#    - set: 'red', 'green', 'blue'
# 2. Run doctests - all must succeed

# %% Polish
# 1. Stwórz zagnieżdżoną listę `result` z elementami:
#    - tuple: 1, 2, 3
#    - list: 1.1, 2.2, 3.3
#    - set: 'red', 'green', 'blue'
# 2. Uruchom doctesty - wszystkie muszą się powieść

# %% Doctests
"""
>>> import sys; sys.tracebacklimit = 0
>>> assert sys.version_info >= (3, 9), \
'Python 3.9+ required'

>>> assert result is not Ellipsis, \
'Assign your result to variable `result`'
>>> assert type(result) is list, \
'Variable `result` has invalid type, should be list'
>>> assert len(result) == 3, \
'Variable `result` length should be 3'

>>> assert (1, 2, 3) in result
>>> assert [1.1, 2.2, 3.3] in result
>>> assert {'red', 'green', 'blue'} in result
"""

# %% Run
# - PyCharm: right-click in the editor and `Run Doctest in ...`
# - PyCharm: keyboard shortcut `Control + Shift + F10`
# - Terminal: `python -m doctest -v myfile.py`

# %% Imports

# %% Types
result: list[tuple|list|set]

# %% Data

# %% Result
result = ...