# libtmux._internal.query_list.QueryList

- **Module:** libtmux._internal.query_list
- **Package:** libtmux
- **Language:** Python
- **Kind:** class
- **Source:** https://github.com/tmux-python/libtmux/blob/036c521c4b83ce6e434eb50afe2a0d08a6a05e46/src/libtmux/_internal/query_list.py#L327
- **Page:** https://libtmux.org/reference/py/libtmux-_internal-query_list-querylist/

Filter list of object/dictionaries. For small, local datasets.

*Experimental, unstable*.

**With dictionaries**:

>>> query = QueryList(
...     [
...         {
...             "place": "Largo",
...             "city": "Tampa",
...             "state": "Florida",
...             "foods": {"fruit": ["banana", "orange"], "breakfast": "cereal"},
...         },
...         {
...             "place": "Chicago suburbs",
...             "city": "Elmhurst",
...             "state": "Illinois",
...             "foods": {"fruit": ["apple", "cantelope"], "breakfast": "waffles"},
...         },
...     ]
... )

>>> query.filter(place="Chicago suburbs")[0]['city']
'Elmhurst'
>>> query.filter(place__icontains="chicago")[0]['city']
'Elmhurst'
>>> query.filter(foods__breakfast="waffles")[0]['city']
'Elmhurst'
>>> query.filter(foods__fruit__in="cantelope")[0]['city']
'Elmhurst'
>>> query.filter(foods__fruit__in="orange")[0]['city']
'Tampa'

>>> query.filter(foods__fruit__in="apple")
[{'place': 'Chicago suburbs',
    'city': 'Elmhurst',
    'state': 'Illinois',
    'foods':
        {'fruit': ['apple', 'cantelope'], 'breakfast': 'waffles'}}]

>>> query.filter(foods__fruit__in="non_existent")
[]

**With objects**:

>>> from typing import Any, Dict
>>> from dataclasses import dataclass, field

>>> @dataclass()
... class Restaurant:
...     place: str
...     city: str
...     state: str
...     foods: Dict[str, Any]

>>> restaurant = Restaurant(
...     place="Largo",
...     city="Tampa",
...     state="Florida",
...     foods={
...         "fruit": ["banana", "orange"], "breakfast": "cereal"
...     }
... )

>>> restaurant
Restaurant(place='Largo',
    city='Tampa',
    state='Florida',
    foods={'fruit': ['banana', 'orange'], 'breakfast': 'cereal'})

>>> query = QueryList([restaurant])

>>> query.filter(foods__fruit__in="banana")
[Restaurant(place='Largo',
    city='Tampa',
    state='Florida',
    foods={'fruit': ['banana', 'orange'], 'breakfast': 'cereal'})]

>>> query.filter(foods__fruit__in="banana")[0].city
'Tampa'

>>> query.get(foods__fruit__in="banana").city
'Tampa'

**With objects (nested)**:

>>> from typing import List, Optional
>>> from dataclasses import dataclass, field

>>> @dataclass()
... class Food:
...     fruit: List[str] = field(default_factory=list)
...     breakfast: Optional[str] = None

>>> @dataclass()
... class Restaurant:
...     place: str
...     city: str
...     state: str
...     food: Food = field(default_factory=Food)

>>> query = QueryList([
...     Restaurant(
...         place="Largo",
...         city="Tampa",
...         state="Florida",
...         food=Food(
...             fruit=["banana", "orange"], breakfast="cereal"
...         )
...     ),
...     Restaurant(
...         place="Chicago suburbs",
...         city="Elmhurst",
...         state="Illinois",
...         food=Food(
...             fruit=["apple", "cantelope"], breakfast="waffles"
...         )
...     )
... ])

>>> query.filter(food__fruit__in="banana")
[Restaurant(place='Largo',
    city='Tampa',
    state='Florida',
    food=Food(fruit=['banana', 'orange'], breakfast='cereal'))]

>>> query.filter(food__fruit__in="banana")[0].city
'Tampa'

>>> query.get(food__fruit__in="banana").city
'Tampa'

>>> query.filter(food__breakfast="waffles")
[Restaurant(place='Chicago suburbs',
    city='Elmhurst',
    state='Illinois',
    food=Food(fruit=['apple', 'cantelope'], breakfast='waffles'))]

>>> query.filter(food__breakfast="waffles")[0].city
'Elmhurst'

>>> query.filter(food__breakfast="non_existent")
[]

## Members

- `data` (attribute)
- `pk_key` (attribute)
- `__init__` (method)
- `items` (method)
- `__eq__` (method)
- `filter` (method) — Filter list of objects.
- `get` (method) — Retrieve exactly one object.