updated link
I failed to notice that the link I added in commit
was to a specific outdated version
@@ -37,7 +37,7 @@ Colors:
'k' black and
'w' white.
'C0'...'C9' the colors defined by the current style
-https://matplotlib.org/2.1.2/api/_as_gen/matplotlib.pyplot.plot.html.
+https://matplotlib.org/api/_as_gen/matplotlib.pyplot.plot.html
If the first character of fmt is a '|' stem is used instead of plot.
