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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_task_cost(self, task_name):
 """ Get task cost :param task_name: name of the task :return: task cost :rtype: Instance.TaskCost :Example: 200 4096 0 """

        summary = self.get_task_summary(task_name)
        if summary is None:
            return None

        if 'Cost' in summary:
            task_cost = summary['Cost']

            cpu_cost = task_cost.get('CPU')
            memory = task_cost.get('Memory')
            input_size = task_cost.get('Input')

            return Instance.TaskCost(cpu_cost, memory, input_size)