public lr_document ObtainDocByID(string docId)
{
Dictionary<string, object> args = new Dictionary<string, object>();
args["by_doc_ID"] = true;
var result = LRUtils.Obtain(_baseUri, docId, args, this.Username, this.Password);
if(result.documents.Count < 1)
throw new Exception("Document with id "+docId+" does not exist.");
return result.documents[0].document[0];
}