Updating example

Author: ifilot

examples/ch4_contour.py

@@ -4,4 +4,4 @@
 res = HF(mol, 'sto3g').rhf(verbose=True)
 
 up = [0,0,1]
-ContourPlotter.build_contourplot(res, 'ch4.png', [0,1,2,up], 3, 101, 3, 3)
+ContourPlotter.build_contourplot(res, 'ch4.png', (0,1,2,up), 3, 101, 3, 3)