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let createDocument: ( WebAPI.DOMAPI.domImplementation, ~namespace: string, ~qualifiedName: string, ~doctype: WebAPI.DOMAPI.documentType=?,) => WebAPI.DOMAPI.xmlDocument
let createDocumentType: ( WebAPI.DOMAPI.domImplementation, ~qualifiedName: string, ~publicId: string, ~systemId: string,) => WebAPI.DOMAPI.documentType
let createHTMLDocument: ( WebAPI.DOMAPI.domImplementation, ~title: string=?,) => WebAPI.DOMAPI.document