Merge pull request #6739 from abergeron/fix_doc_warning

fix doc warning

Merge pull request #6739 from abergeron/fix_doc_warning
b50ba163 · Frédéric Bastien · GitHub · cdeb9afd · a9fc4620 · b50ba163
--- a/doc/extending/extending_theano.txt
+++ b/doc/extending/extending_theano.txt
@@ -791,7 +791,7 @@ implementation.
 It takes an optional :func:`infer_shape` parameter that must have this
 signature:
-.. code-block:: python
+.. code-block:: none
    def infer_shape(node, input_shapes):
        # ...