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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 client_tokens(self):
 """try and get Oauth 2.0 client id and secret first from basic auth header, then from GET or POST parameters return -- tuple -- client_id, client_secret """

        client_id, client_secret = self.get_auth_basic()
        if not client_id and not client_secret:
            client_id = self.query_kwargs.get('client_id', '')
            client_secret = self.query_kwargs.get('client_secret', '')
            if not client_id and not client_secret:
                client_id = self.body_kwargs.get('client_id', '')
                client_secret = self.body_kwargs.get('client_secret', '')

        return client_id, client_secret