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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_access_key(self):
 """ Gets the application secret key. The value can be stored in parameters "access_key", "client_key" or "secret_key". :return: the application secret key. """

        access_key = self.get_as_nullable_string("access_key")
        access_key = access_key if access_key != None else self.get_as_nullable_string("access_key")
        return access_key