ExternalLinks namespace has been removed from EXM and no similar code is available in any Sirecore.EmailCampaign.* v3.5.180411 nuget packages. How i can achieveExternalLinks.DatabaseToItem functionality in EXM 3.5 u2 rev.180411 ?

I have used Sitecore.Modules.EmailCampaign.Core.ExternalLinks.DatabaseToItem(args.Message); code in previous version of EXM and now upgraded to EXM 3.5 u2 rev.180411 and getting the error after upgrade it seems like ExternalLinks namespace has been removed from EXM and no similar code is available in any Sirecore.EmailCampaign.* v3.5.180411 nuget packages. How i can achieve ExternalLinks.DatabaseToItem method functionality in EXM 3.5 u2 rev.180411 ?