Get current opened browser window in selenium 2 (WebDriver)

I am using selenium 2 (WebDriver) now and I would like to get the control of current opened browse开发者_高级运维r window instead of open a new one. That means I can't use driver.get("url") which is showed in all online documents. Could anyone help?

FYI, I am using Python binding of selenium and firefox. Thanks.

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Unfortunately you can't connect to an open browser at the moment. There is an open bug for WebDriver to support that