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# delegate

The delegate assigned when this object was created.

```
var delegate: (any URLSessionDelegate)? { get }
```

## Discussion

This delegate object is responsible for handling authentication challenges, for making caching decisions, and for handling other session-related events. The session object keeps a strong reference to this delegate until your app exits or explicitly invalidates the session. If you do not invalidate the session, your app leaks memory until it exits.

> Note:
> This delegate object must be set at object creation time and may not be changed.

---

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