Add subprocess deprecation message

dstansby · dstansby · commit d8150838b880 · 2018-02-24T21:36:33.000Z
diff --git a/lib/matplotlib/compat/subprocess.py b/lib/matplotlib/compat/subprocess.py
@@ -10,6 +10,13 @@
 This module is safe to import from anywhere within matplotlib.
 """
 import subprocess
+from matplotlib.cbook import warn_deprecated
+warn_deprecated(since='3.0',
+                name='matplotlib.compat.subprocess',
+                alternative='All the functionality provided by this module '
+                            'is available in the python 3 standard library '
+                            '"subprocess" module.',
+                obj_type='module')
 
 __all__ = ['Popen', 'PIPE', 'STDOUT', 'check_output', 'CalledProcessError']
 
