fix when no legend-loc is given

src/plot.py

@@ -371,6 +371,9 @@ def plot(
 
     ax.set_title(title)
     if show_legend:
+        if legend_loc == []:
+            ax.legend(loc=None)
+        else:
             ax.legend(loc=legend_loc[0])
 
         extra_legends = []