Add deprecation warnings

Author: martinRenou

ipykernel/pylab/backend_inline.py

@@ -3,4 +3,13 @@
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
+import warnings
+
 from matplotlib_inline.backend_inline import * # analysis: ignore
+
+
+warnings.warn(
+    "`ipykernel.pylab.backend_inline` is deprecated, directly "
+    "use `matplotlib_inline.backend_inline`",
+    DeprecationWarning
+)

ipykernel/pylab/config.py

@@ -3,4 +3,13 @@
 This module does not import anything from matplotlib.
 """
 
+import warnings
+
 from matplotlib_inline.config import * # analysis: ignore
+
+
+warnings.warn(
+    "`ipykernel.pylab.config` is deprecated, directly "
+    "use `matplotlib_inline.config`",
+    DeprecationWarning
+)