code: func (c *CloudFormation) CancelUpdateStack(input *CancelUpdateStackInput) (*CancelUpdateStackOutput, error) {
  	req, out := c.CancelUpdateStackRequest(input)
  	return out, req.Send()
  }
docs: // CancelUpdateStack API operation for AWS CloudFormation.
  //
  // Cancels an update on the specified stack. If the call completes successfully,
  // the stack rolls back the update and reverts to the previous stack configuration.
  //
  // You can cancel only stacks that are in the UPDATE_IN_PROGRESS state.
  //
  // Returns awserr.Error for service API and SDK errors. Use runtime type assertions
  // with awserr.Error's Code and Message methods to get detailed information about
  // the error.
  //
  // See the AWS API reference guide for AWS CloudFormation's
  // API operation CancelUpdateStack for usage and error information.
  //
  // Returned Error Codes:
  //   * ErrCodeTokenAlreadyExistsException "TokenAlreadyExistsException"
  //   A client request token already exists.
  //
  // See also, https://docs.aws.amazon.com/goto/WebAPI/cloudformation-2010-05-15/CancelUpdateStack