Electrum 2.x sweep feature Could some explain how Electrum sweep feature works?

As I understand "sweep" can be used only after importing private key into wallet. But private key can't be imported into deterministic Electrum 2.x wallet.

So why it shows me sweep option?

It there any ways to sweep paper wallet into deterministic Electrum wallet?
The sweep function will send all coins related to the imported private key(s) to a new address (from the deterministic wallet). After sweeping, the private key is no longer capable of spending coins.

There is no need to "import" the private key in advance.

Mind that you need to pay a fee for the sweeping transaction (which is very little).