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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 is_sufficient(self, device):
 """ Returns whether the device is sufficient for this requirement. :param device: A GPUDevice instance. :type device: GPUDevice :return: True if the requirement is fulfilled otherwise False """


        sufficient = True
        if (self.min_vram is not None) and (device.vram < self.min_vram):
            sufficient = False

        return sufficient