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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 create_stack(self, stack_name, template_body=None, template_url=None, parameters=[], notification_arns=[], disable_rollback=False, timeout_in_minutes=None, capabilities=None):
 """ Creates a CloudFormation Stack as specified by the template. :type stack_name: string :param stack_name: The name of the Stack, must be unique amoung running Stacks :type template_body: string :param template_body: The template body (JSON string) :type template_url: string :param template_url: An S3 URL of a stored template JSON document. If both the template_body and template_url are specified, the template_body takes precedence :type parameters: list of tuples :param parameters: A list of (key, value) pairs for template input parameters. :type notification_arns: list of strings :param notification_arns: A list of SNS topics to send Stack event notifications to. :type disable_rollback: bool :param disable_rollback: Indicates whether or not to rollback on failure. :type timeout_in_minutes: int :param timeout_in_minutes: Maximum amount of time to let the Stack spend creating itself. If this timeout is exceeded, the Stack will enter the CREATE_FAILED state. :type capabilities: list :param capabilities: The list of capabilities you want to allow in the stack. Currently, the only valid capability is 'CAPABILITY_IAM'. :rtype: string :return: The unique Stack ID. """

        params = {'ContentType': "JSON", 'StackName': stack_name,
                'DisableRollback': self.encode_bool(disable_rollback)}
        if template_body:
            params['TemplateBody'] = template_body
        if template_url:
            params['TemplateURL'] = template_url
        if template_body and template_url:
            boto.log.warning("If both TemplateBody and TemplateURL are"
                " specified, only TemplateBody will be honored by the API")
        if len(parameters) > 0:
            for i, (key, value) in enumerate(parameters):
                params['Parameters.member.%d.ParameterKey' % (i+1)] = key
                params['Parameters.member.%d.ParameterValue' % (i+1)] = value
        if capabilities:
            for i, value in enumerate(capabilities):
                params['Capabilities.member.%d' % (i+1)] = value
        if len(notification_arns) > 0:
            self.build_list_params(params, notification_arns,
                                   "NotificationARNs.member")
        if timeout_in_minutes:
            params['TimeoutInMinutes'] = int(timeout_in_minutes)

        response = self.make_request('CreateStack', params, '/', 'POST')
        body = response.read()
        if response.status == 200:
            body = json.loads(body)
            return body['CreateStackResponse']['CreateStackResult']['StackId']
        else:
            boto.log.error('%s %s' % (response.status, response.reason))
            boto.log.error('%s' % body)
            raise self.ResponseError(response.status, response.reason, body)