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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_user_env_vars(self):

 """Return the user defined environment variables"""

        return (os.environ.get(self.GP_URL_ENV_VAR),
            os.environ.get(self.GP_INSTANCE_ID_ENV_VAR),
            os.environ.get(self.GP_USER_ID_ENV_VAR),
            os.environ.get(self.GP_PASSWORD_ENV_VAR),
            os.environ.get(self.GP_IAM_API_KEY_ENV_VAR))