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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 get_first_webview_context(self):
 """Return the first WEBVIEW context or raise an exception if it is not found :returns: first WEBVIEW context """

        for context in self.driver_wrapper.driver.contexts:
            if context.startswith('WEBVIEW'):
                return context
        raise Exception('No WEBVIEW context has been found')