update example docstring of afm.py

ImportanceOfBeingErnest · web-flow · commit 551d9e9aaa2b · 2018-02-15T02:17:10.000+01:00
In order for the example to work in python 3, the file needs to be read in binary mode: `open(afm_fname, 'rb')`
diff --git a/lib/matplotlib/afm.py b/lib/matplotlib/afm.py
@@ -19,7 +19,7 @@
     ...                         'fonts', 'afm', 'ptmr8a.afm')
     >>>
     >>> from matplotlib.afm import AFM
-    >>> with open(afm_fname) as fh:
+    >>> with open(afm_fname, 'rb') as fh:
     ...     afm = AFM(fh)
     >>> afm.string_width_height('What the heck?')
     (6220.0, 694)
