Add a matplotlib hy example, reproduces a weird hanging issue

Author: Olical

dev/hy/matplot-demo.hy

@@ -0,0 +1,21 @@
+(+ 10 20)
+
+(import matplotlib)
+(.use matplotlib "Qt5Agg")
+(.rcdefaults matplotlib)
+(.use matplotlib "Qt5Agg")
+
+(import [matplotlib [pyplot]])
+
+(.ion pyplot)
+(pyplot.style.use "default")
+(pyplot.style.use "fivethirtyeight")
+
+(defn test []
+ "Plot a list."
+ (setv fig (.figure pyplot))
+ (setv axes (.add_subplot fig))
+ (.plot axes (list (range 20)))
+ {:figure fig :axes axes})
+
+(test)