Move a comment from the documentation into the example that it refers to, in...

Move a comment from the documentation into the example that it refers to, in order to avoid inconsistencies (e.g. line number references) and also to make it visible to those who only look at the file.
See #2353.

docs/examples/tutorial/memory_allocation/malloc.pyx

@@ -13,6 +13,10 @@ def random_noise(int number=1):
         for i in range(number):
             my_array[i] = ran(0, 1)
 
+        # ... let's just assume we do some more heavy C calculations here to make up
+        # for the work that it takes to pack the C double values into Python float
+        # objects below, right after throwing away the existing objects above.
+
         return [x for x in my_array[:number]]
     finally:
         # return the previously allocated memory to the system

docs/src/tutorial/memory_allocation.rst

@@ -37,14 +37,6 @@ A very simple example of malloc usage is the following:
 .. literalinclude:: ../../examples/tutorial/memory_allocation/malloc.pyx
     :linenos:
 
-.. note::
-
-    Here we take Python doubles (with ``ran(0, 1)``) and convert
-    them to C doubles when putting them in ``my_array``. After that,
-    we put them back into a Python list at line 19. So those C doubles
-    are converted again into Python doubles. This is highly inefficient,
-    and only for demo purposes.
-
 Note that the C-API functions for allocating memory on the Python heap
 are generally preferred over the low-level C functions above as the
 memory they provide is actually accounted for in Python's internal