# collections.abs模块中的抽象基类

在`collections.abc` 模块中定义了16个抽象基类，简要的UML类图。

```mermaid
classDiagram
Iterable <|-- Iterator
Iterable <|-- Sequence
Iterable <|-- Mapping
Iterable <|-- Set
Iterable <|-- MappingView
Container <|-- Sequence
Container <|-- Mapping
Container <|-- Set
Sized <|-- Sequence
Sized <|-- Mapping
Sized <|-- Set
Sized <|-- MappingView
Sequence <|-- MutableSequence
Mapping <|-- MutableMapping
Set <|-- MutableSet
Set <|-- ItemsView
Set <|-- KeysView
MappingView <|-- ItemsView
MappingView <|-- KeysView
MappingView <|-- ValuesView
class Callable
class Hashable
```



| ABC               | Inherits from                    | Abstract Methods                                             | Mixin Methods                                                |
| :---------------- | :------------------------------- | :----------------------------------------------------------- | :----------------------------------------------------------- |
| `Container`       |                                  | `__contains__`                                               |                                                              |
| `Hashable`        |                                  | `__hash__`                                                   |                                                              |
| `Iterable`        |                                  | `__iter__`                                                   |                                                              |
| `Iterator`        | `Iterable`                       | `__next__`                                                   | `__iter__`                                                   |
| `Reversible`      | `Iterable`                       | `__reversed__`                                               |                                                              |
| `Generator`       | `Iterator`                       | `send`, `throw`                                              | `close`, `__iter__`, `__next__`                              |
| `Sized`           |                                  | `__len__`                                                    |                                                              |
| `Callable`        |                                  | `__call__`                                                   |                                                              |
| `Collection`      | `Sized`, `Iterable`, `Container` | `__contains__`, `__iter__`, `__len__`                        |                                                              |
| `Sequence`        | `Reversible`, `Collection`       | `__getitem__`, `__len__`                                     | `__contains__`, `__iter__`, `__reversed__`, `index`, and `count` |
| `MutableSequence` | `Sequence`                       | `__getitem__`, `__setitem__`, `__delitem__`, `__len__`, `insert` | Inherited `Sequence` methods and `append`, `reverse`, `extend`, `pop`, `remove`, and `__iadd__` |
| `ByteString`      | `Sequence`                       | `__getitem__`, `__len__`                                     | Inherited `Sequence` methods                                 |
| `Set`             | `Collection`                     | `__contains__`, `__iter__`, `__len__`                        | `__le__`, `__lt__`, `__eq__`, `__ne__`, `__gt__`, `__ge__`, `__and__`, `__or__`, `__sub__`, `__xor__`, and `isdisjoint` |
| `MutableSet`      | `Set`                            | `__contains__`, `__iter__`, `__len__`, `add`, `discard`      | Inherited `Set` methods and `clear`, `pop`, `remove`, `__ior__`, `__iand__`, `__ixor__`, and `__isub__` |
| `Mapping`         | `Collection`                     | `__getitem__`, `__iter__`, `__len__`                         | `__contains__`, `keys`, `items`, `values`, `get`, `__eq__`, and `__ne__` |
| `MutableMapping`  | `Mapping`                        | `__getitem__`, `__setitem__`, `__delitem__`, `__iter__`, `__len__` | Inherited `Mapping` methods and `pop`, `popitem`, `clear`, `update`, and `setdefault` |
| `MappingView`     | `Sized`                          |                                                              | `__len__`                                                    |
| `ItemsView`       | `MappingView`, `Set`             |                                                              | `__contains__`, `__iter__`                                   |
| `KeysView`        | `MappingView`, `Set`             |                                                              | `__contains__`, `__iter__`                                   |
| `ValuesView`      | `MappingView`, `Collection`      |                                                              | `__contains__`, `__iter__`                                   |
| `Awaitable`       |                                  | `__await__`                                                  |                                                              |
| `Coroutine`       | `Awaitable`                      | `send`, `throw`                                              | `close`                                                      |
| `AsyncIterable`   |                                  | `__aiter__`                                                  |                                                              |
| `AsyncIterator`   | `AsyncIterable`                  | `__anext__`                                                  | `__aiter__`                                                  |
| `AsyncGenerator`  | `AsyncIterator`                  | `asend`, `athrow`                                            | `aclose`, `__aiter__`, `__anext__`                           |
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