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# Errors

Pydantic-specific errors.

## PydanticErrorMixin

A mixin class for common functionality shared by all Pydantic-specific errors.

### Attributes

#### message

A message describing the error.

#### code

An optional error code from PydanticErrorCodes enum.

## PydanticUserError

**Bases:** `PydanticErrorMixin`, [`RuntimeError`](https://docs.python.org/3/builtins/exceptions.html#RuntimeError)

An error raised due to incorrect use of Pydantic.

## PydanticUndefinedAnnotation

**Bases:** `PydanticErrorMixin`, [`NameError`](https://docs.python.org/3/builtins/exceptions.html#NameError)

A subclass of `NameError` raised when handling undefined annotations during `CoreSchema` generation.

### Attributes

#### name

Name of the error.

#### message

Description of the error.

### Methods

#### from\_name\_error

`@classmethod`

```python
def from_name_error(cls, name_error: NameError) -> Self
```

Convert a `NameError` to a `PydanticUndefinedAnnotation` error.

##### Returns

[`Self`](https://docs.python.org/3/library/typing.html#typing.Self) -- Converted `PydanticUndefinedAnnotation` error.

##### Parameters

**`name_error`** : [`NameError`](https://docs.python.org/3/builtins/exceptions.html#NameError)

`NameError` to be converted.

## PydanticImportError

**Bases:** `PydanticErrorMixin`, [`ImportError`](https://docs.python.org/3/builtins/exceptions.html#ImportError)

An error raised when an import fails due to module changes between V1 and V2.

### Attributes

#### message

Description of the error.

## PydanticSchemaGenerationError

**Bases:** [`PydanticUserError`](/guides/pydantic-errors#pydanticusererror)

An error raised during failures to generate a `CoreSchema` for some type.

### Attributes

#### message

Description of the error.

## PydanticInvalidForJsonSchema

**Bases:** [`PydanticUserError`](/guides/pydantic-errors#pydanticusererror)

An error raised during failures to generate a JSON schema for some `CoreSchema`.

### Attributes

#### message

Description of the error.

## PydanticForbiddenQualifier

**Bases:** [`PydanticUserError`](/guides/pydantic-errors#pydanticusererror)

An error raised if a forbidden type qualifier is found in a type annotation.

## Related pages

- [API Documentation](./api-documentation-index.md)
- [Concepts](./concepts-index.md)
- [Dev Tools](./dev-tools-index.md)
- [Error Messages](./error-messages-index.md)
- [Examples](./examples-index.md)
- [Integrations](./integrations-index.md)
- [Internals](./internals-index.md)
- [Production Tools](./production-tools-index.md)
- [Pydantic](./pydantic-index.md)
- [Pydantic Core](./pydantic-core-index.md)

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