Update explanation for named_arg

tests/failing_tests/named_arg.py

@@ -4,6 +4,12 @@ from pythonbpf.maps import HashMap
 
 from ctypes import c_void_p, c_int64
 
+# NOTE: This example exposes the problems with our typing system.
+# We can't do steps on line 25 and 27.
+# prev is of type i64**. For prev + 1, we deref it down to i64
+# To assign it back to prev, we need to go back to i64**.
+# We cannot allocate space for the intermediate type now.
+# We probably need to track the ref/deref chain for each variable.
 
 @bpf
 @map