Property 'beginBatch' does not exist on type 'SPHttpClient'

Hello - I'm trying to use OfficeUIFabricPeoplePicker, below is snippet which has error around beginbatch. 

Upon further research, I found post which says  spHttpClient.beginBatch is still in preview so it has now been moved to the plusbeta channel in SPFx.  https://github.com/SharePoint/sp-dev-docs/issues/1956. 

I'm using spfx 1.7.0 and spHttpClient.beginBatch is still in preview ? If so, is there any replacement ? 

Thanks in advance.