# Collections

There are several collection providers: `List` and `Dict`

## List

- List provider contains other providers.
- Resolves into an immutable sequence of dependencies.

```python
import random
from that_depends import BaseContainer, providers


class DIContainer(BaseContainer):
    random_number = providers.Factory(random.random)
    numbers_sequence = providers.List(random_number, random_number)


DIContainer.numbers_sequence.resolve_sync()
# (0.3035656170071561, 0.8280498192037787)
```

## Dict

- Dict provider is a collection of named providers.
- Resolves into a read-only mapping of dependencies.

```python
import random
from that_depends import BaseContainer, providers


class DIContainer(BaseContainer):
    random_number = providers.Factory(random.random)
    numbers_map = providers.Dict(key1=random_number, key2=random_number)


DIContainer.numbers_map.resolve_sync()
# mappingproxy({'key1': 0.6851384528299208, 'key2': 0.41044920948045294})
```