diff --git a/prometheus/testutil/testutil.go b/prometheus/testutil/testutil.go
index 3acb8ef..6145833 100644
--- a/prometheus/testutil/testutil.go
+++ b/prometheus/testutil/testutil.go
@@ -19,9 +19,11 @@ import (
 	"reflect"
 	"sort"
 
-	"github.com/prometheus/client_golang/prometheus"
-	dto "github.com/prometheus/client_model/go"
 	"github.com/prometheus/common/expfmt"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/prometheus/client_golang/prometheus"
 )
 
 // GatherAndCompare retrieves all metrics exposed by a collector and compares it