# devtools

:::callout{intent="note"}
**Admission:** I (the primary developer of Pydantic) also develop python-devtools.
:::

[python-devtools](https://python-devtools.helpmanual.io/) (`pip install devtools`) provides a number of tools which
are useful during Python development, including `debug()` an alternative to `print()` which formats output in a way
which should be easier to read than `print` as well as giving information about which file/line the print statement
is on and what value was printed.

Pydantic integrates with _devtools_ by implementing the `__pretty__` method on most public classes.

In particular `debug()` is useful when inspecting models:

```python
from datetime import datetime

from devtools import debug

from pydantic import BaseModel


class Address(BaseModel):
    street: str
    country: str
    lat: float
    lng: float


class User(BaseModel):
    id: int
    name: str
    signup_ts: datetime
    friends: list[int]
    address: Address


user = User(
    id='123',
    name='John Doe',
    signup_ts='2019-06-01 12:22',
    friends=[1234, 4567, 7890],
    address=dict(street='Testing', country='uk', lat=51.5, lng=0),
)
debug(user)
print('\nshould be much easier read than:\n')
print('user:', user)
```

Will output in your terminal:

{}

`debug()` is a development-time tool: it prints to the terminal of a process you're watching. The
closest equivalent for a deployed application is [Logfire](/guides/integrations-logfire), where models and validations
show up as structured output you can browse and query.

## 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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