the code is self.close(); some times the window is closed and sometime it doesn't closed and not throwing any popup or alert. So i wanted to check whether the window is closed or still open? How it can be done through selenium?
Assuming I understand your question correctly... You should store the ID (of the window you're trying to close) in a variable.
After calling the close method, check if the window ID still exists. If it does, something went wrong.
Example in C#. Instead of the String.Equals check, you can also get a list of all windowHandles and check if the specific handle is still in it. Edit: didn't test this, just an idea to get you going.
string handle = driver.CurrentWindowHandle; driver.Close(); if (String.Equals(handle, driver.CurrentWindowHandle)) throw new Exception("Not closed!");