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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 parse_stack(self, global_params, region, stack):
 """ Parse a single stack and fetch additional attributes :param global_params: Parameters shared for all regions :param region: Name of the AWS region :param stack_url: URL of the AWS stack """

        stack['id'] = stack.pop('StackId')
        stack['name'] = stack.pop('StackName')
        stack_policy = api_clients[region].get_stack_policy(StackName = stack['name'])
        if 'StackPolicyBody' in stack_policy:
            stack['policy'] = json.loads(stack_policy['StackPolicyBody'])
        self.stacks[stack['name']] = stack