Return a string which is a token, needed for some API calls
        :return: Token (can be used with some API call
        :rtype: str

        .. todo:: make a token class to be able to store date of expiration

def get_token(self):
        """
        Return a string which is a token, needed for some API calls
        :return: Token (can be used with some API call
        :rtype: str

        .. todo:: make a token class to be able to store date of expiration
        """
        self.bbox_auth.set_access(BboxConstant.AUTHENTICATION_LEVEL_PRIVATE, BboxConstant.AUTHENTICATION_LEVEL_PRIVATE)
        self.bbox_url.set_api_name(BboxConstant.API_DEVICE, "token")
        api = BboxApiCall(self.bbox_url, BboxConstant.HTTP_METHOD_GET, None,
                          self.bbox_auth)
        resp = api.execute_api_request()
        return resp.json()[0]['device']['token']