spray set content-type for XML

Question

When trying to send an xml content-type Mime-header

sender ! HttpResponse(status = 200, entity = responseBody, headers = List(`Content-Type`(`text/xml`)))

I get the error:

not found: value text/xml

I tried with application/xml which did not work either, application/json works FWIW

Is there some import missing?

Edit: tried to add this

import spray.http.MediaTypes._
sender ! HttpResponse(status = 400, entity = responseBody, headers = List(`Content-Type`(`application/xml`)))

this gave the following error:

Explicitly set response header 'Content-Type: application/xml' is 
ignored, the response Content-Type is set via the response's HttpEntity!

Answer 1

import spray.http.HttpEntity    
sender ! HttpResponse(status = 200, entity = httpEntity(`application/xml`,responseBody))

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