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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def screenshot(self):
 """ Take screenshot with session check Returns: PIL.Image """

        b64data = self.http.get('/screenshot').value
        raw_data = base64.b64decode(b64data)
        from PIL import Image
        buff = io.BytesIO(raw_data)
        return Image.open(buff)