Format code, update documentation and remove exported variable `XMLHeaderByte`

1 files changed, 1 insertions, 1 deletions

diff --git a/drawing.go b/drawing.go
index e3e7fa8..1daa912 100644
--- a/drawing.go
+++ b/drawing.go
@@ -740,7 +740,7 @@ func (f *File) drawChartShape(formatSet *formatChart) *attrValString {
 // drawChartSeries provides a function to draw the c:ser element by given
 // format sets.
 func (f *File) drawChartSeries(formatSet *formatChart) *[]cSer {
-	ser := []cSer{}
+	var ser []cSer
 	for k := range formatSet.Series {
 		ser = append(ser, cSer{
 			IDx:   &attrValInt{Val: intPtr(k + formatSet.order)},