Sets the user settings like multi-factor authentication (MFA). If MFA is to be removed for a particular attribute pass the attribute with code delivery as null. If null list is passed, all MFA options are removed.
/// This exception is thrown when Amazon Cognito encounters an internal error.
///
/// This exception is thrown when the Amazon Cognito service encounters an invalid parameter.
///
/// This exception gets thrown when a user is not authorized.
///
/// This exception is thrown when a password reset is required.
///
/// This exception is thrown when the Amazon Cognito service cannot find the requested
/// resource.
///
/// This exception is thrown when a user is not confirmed successfully.
///
/// This exception is thrown when a user is not found.
///
