9.7. Idiom Vars

  • vars([object])

  • Without arguments, equivalent to locals()

  • With an argument, equivalent to object.__dict__

9.7.1. SetUp

>>> class User:
...     def __init__(self, firstname, lastname):
...         self.firstname = firstname
...         self.lastname = lastname
...
...     def login(self):
...         return 'logged-in'
...
...     def logout(self):
...         return 'logged-out'

9.7.2. Class

>>> vars(User)
mappingproxy({
    '__module__': '__main__',
    '__firstlineno__': 1,
    '__init__': <function User.__init__ at 0x...>,
    'login': <function User.login at 0x...>,
    'logout': <function User.logout at 0x...>,
    '__static_attributes__': ('firstname', 'lastname'),
    '__dict__': <attribute '__dict__' of 'User' objects>,
    '__weakref__': <attribute '__weakref__' of 'User' objects>,
    '__doc__': None})

9.7.3. Instance

>>> alice = User('Alice', 'Apricot')
>>>
>>> vars(alice)
{'firstname': 'Alice', 'lastname': 'Apricot'}

9.7.4. Vars vs __dict__

  • The same

  • Function vars() use __dict__ for the result

  • Using vars() is preferred

>>> alice = User('Alice', 'Apricot')
>>>
>>> vars(alice)
{'firstname': 'Alice', 'lastname': 'Apricot'}
>>>
>>> alice.__dict__
{'firstname': 'Alice', 'lastname': 'Apricot'}

9.7.5. Usage

  • keys

  • values

>>> keys = list(vars(alice).keys())
>>> values = list(vars(alice).values())
>>>
>>> print(keys)
['firstname', 'lastname']
>>>
>>> print(values)
['Alice', 'Apricot']

9.7.6. Assignments

# %% About
# - Name: Idiom Vars Object
# - Difficulty: easy
# - Lines: 1
# - Minutes: 2

# %% 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. Get state of `alice` object (all attributes and values in dict format)
# 2. Define `result: dict` with the result
# 3. Run doctests - all must succeed

# %% Polish
# 1. Pobierz stan obiektu `alice` (wszystkie atrybuty i wartości w formacie dict)
# 2. Zdefiniuj `result: dict` z wynikiem
# 3. Uruchom doctesty - wszystkie muszą się powieść

# %% Example
# >>> result
# {'username': 'alice', 'password': 'secret', 'authenticated': False}

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

>>> from pprint import pprint
>>> from inspect import isclass

>>> assert isclass(User)
>>> assert isinstance(alice, User)
>>> assert hasattr(alice, 'username')
>>> assert hasattr(alice, 'password')
>>> assert hasattr(alice, 'authenticated')
>>> assert getattr(alice, 'username') == 'alice'

>>> assert getattr(alice, 'password') == 'secret'

>>> assert getattr(alice, 'authenticated') is False

>>> assert type(result) is dict
>>> assert len(result) == 3
>>> assert 'username' in result
>>> assert 'password' in result
>>> assert 'authenticated' in result

>>> result
{'username': 'alice', 'password': 'secret', 'authenticated': False}
"""

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

# %% Imports

# %% Types
result: dict[str, str|bool]

# %% Data
class User:
    def __init__(self, username, password):
        self.username = username
        self.password = password
        self.authenticated = False

    def login(self):
        self.authenticated = True

    def logout(self):
        self.authenticated = False


alice = User('alice', 'secret')

# %% Result
result = ...


# %% About
# - Name: Idiom Vars Class
# - Difficulty: easy
# - Lines: 1
# - Minutes: 2

# %% 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. Get state of `User` class (all attributes and values in dict format)
# 2. Define `result: dict` with the result
# 3. Run doctests - all must succeed

# %% Polish
# 1. Pobierz stan klasy `User` (wszystkie atrybuty i wartości w formacie dict)
# 2. Zdefiniuj `result: dict` z wynikiem
# 3. Uruchom doctesty - wszystkie muszą się powieść

# %% Example
# >>> result
# mappingproxy({'__dict__': <attribute '__dict__' of 'User' objects>,
#               '__doc__': None,
#               '__firstlineno__': 67,
#               '__init__': <function User.__init__ at 0x...>,
#               '__module__': '...',
#               '__static_attributes__': ('authenticated', 'password', 'username'),
#               '__weakref__': <attribute '__weakref__' of 'User' objects>,
#               'login': <function User.login at 0x...>,
#               'logout': <function User.logout at 0x...>})

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

>>> from pprint import pprint
>>> from inspect import isclass

>>> assert isclass(User)

>>> assert '__init__' in result
>>> assert 'login' in result
>>> assert 'logout' in result

>>> pprint(result, width=120)  # doctest: +ELLIPSIS
mappingproxy({'__dict__': <attribute '__dict__' of 'User' objects>,
              '__doc__': None,
              '__firstlineno__': ...,
              '__init__': <function User.__init__ at 0x...>,
              '__module__': '...',
              '__static_attributes__': ('authenticated', 'password', 'username'),
              '__weakref__': <attribute '__weakref__' of 'User' objects>,
              'login': <function User.login at 0x...>,
              'logout': <function User.logout at 0x...>})
"""

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

# %% Imports

# %% Types
result: dict[str, str|bool]

# %% Data
class User:
    def __init__(self, username, password):
        self.username = username
        self.password = password
        self.authenticated = False

    def login(self):
        self.authenticated = True

    def logout(self):
        self.authenticated = False

# %% Result
result = ...