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# Lookup

> Phone Number Lookup namespace.

[restclient]: /docs/server-sdks/reference/python/rest/client

Look up carrier and CNAM information for a phone number. This is useful for
validating phone numbers, identifying carriers, and checking caller name data
before placing calls.

Access via `client.lookup` on a [`RestClient`][restclient] instance.

## **Methods**

#### [phone\_number](/docs/server-sdks/reference/python/rest/lookup/phone-number)

Look up a phone number.

## **Example**

```python {4}
from signalwire.rest import RestClient

client = RestClient()
result = client.lookup.phone_number("+15551234567")
```

> Phone Number Lookup namespace.

## Docs

- [phone_number](https://signalwire.com/docs/server-sdks/reference/python/rest/lookup/phone-number.md): Look up carrier and CNAM information for a phone number.