diff --git a/C/errors.c b/C/errors.c
index fd0411bd6..4e425f652 100755
--- a/C/errors.c
+++ b/C/errors.c
@@ -40,7 +40,9 @@ bool Yap_Warning(const char *s, ...) {
   Term ts[2];
   const char *fmt;
   char tmpbuf[MAXPATHLEN];
+  yap_error_descriptor_t olde;
 
+  Yap_pushErrorContext(&olde);
   LOCAL_DoingUndefp = true;
   LOCAL_within_print_message = true;
   pred = RepPredProp(PredPropByFunc(FunctorPrintMessage,
@@ -53,20 +55,24 @@ bool Yap_Warning(const char *s, ...) {
 #else
     (void)vsprintf(tmpbuf, fmt, ap);
 #endif
-  } else
+  } else {
+    Yap_popErrorContext(false);
     return false;
+  }
   va_end(ap);
   if (pred->OpcodeOfPred == UNDEF_OPCODE || pred->OpcodeOfPred == FAIL_OPCODE) {
     fprintf(stderr, "warning message: %s\n", tmpbuf);
     LOCAL_DoingUndefp = false;
     LOCAL_within_print_message = false;
+    Yap_popErrorContext(false);
     return false;
   }
 
   ts[1] = MkAtomTerm(AtomWarning);
   ts[0] = MkAtomTerm(Yap_LookupAtom(tmpbuf));
   rc = Yap_execute_pred(pred, ts, true PASS_REGS);
-  return rc;
+    Yap_popErrorContext(false);
+    return rc;
 }
 
 void Yap_InitError__(const char *file, const char *function, int lineno, yap_error_number e, Term t, ...) {
diff --git a/packages/python/python.c b/packages/python/python.c
index 75aac7599..28b0c6569 100644
--- a/packages/python/python.c
+++ b/packages/python/python.c
@@ -27,7 +27,8 @@ PyObject *py_ModDict;
 
 VFS_t pystream;
 
-static void *py_open(VFS_t *me, int sno, const char *name,
+static void *
+py_open(VFS_t *me, int sno, const char *name,
                      const char *io_mode) {
 #if HAVE_STRCASESTR
   if (strcasestr(name, "//python/") == name)
@@ -37,6 +38,7 @@ static void *py_open(VFS_t *me, int sno, const char *name,
     name += strlen("//python/");
 #endif
   StreamDesc *st = YAP_RepStreamFromId(sno);
+  fprintf(stderr,"opened %p\n");
   // we assume object is already open, so there is no need to open it.
   PyObject *stream = string_to_python(name, true, NULL);
   if (stream == Py_None)
@@ -44,12 +46,16 @@ static void *py_open(VFS_t *me, int sno, const char *name,
   Py_INCREF(stream);
   st->u.private_data = stream;
   st->vfs = me;
+  if (strchr(io_mode,'r'))
+      st->status = Input_Stream_f;
+      else
   st->status = Append_Stream_f | Output_Stream_f;
   Yap_DefaultStreamOps(st);
   return stream;
 }
 
-static bool py_close(int sno) {
+static bool
+py_close(int sno) {
   return true;
   StreamDesc *s = YAP_GetStreamFromId(sno);
   PyObject *fclose = PyObject_GetAttrString(s->u.private_data, "close");
@@ -58,7 +64,8 @@ static bool py_close(int sno) {
   return v;
 }
 
-static int py_put(int sno, int ch) {
+static int
+py_put(int sno, int ch) {
   // PyObject *pyw; // buffer
   // int pyw_kind;
   // PyObject *pyw_data;
diff --git a/packages/python/swig/yap4py/yapi.py b/packages/python/swig/yap4py/yapi.py
index f80b2a9ed..5c76db4ca 100644
--- a/packages/python/swig/yap4py/yapi.py
+++ b/packages/python/swig/yap4py/yapi.py
@@ -182,7 +182,6 @@ class YAPShell:
         self.port = "call"
         # launch the query
         while self.answer(q):
-            print( self.port )
             if self.port == "exit":
                 # done
                 q.close()
diff --git a/packages/python/yap_kernel/yap_ipython/prolog/jupyter.yap b/packages/python/yap_kernel/yap_ipython/prolog/jupyter.yap
index ef2181c96..711f34fa6 100644
--- a/packages/python/yap_kernel/yap_ipython/prolog/jupyter.yap
+++ b/packages/python/yap_kernel/yap_ipython/prolog/jupyter.yap
@@ -61,12 +61,12 @@ blankc('\n').
 blankc('\t').
 
 enter_cell(_Self) :-
-	%open('//python/input', read, _Input, []),
-	open('//python/sys.stdout', append, _Output, []),
-	open('//python/sys.stdout', append, _Error, []),
-	%set_prolog_flag(user_input, _Input),
-	set_prolog_flag(user_output, _Output),
-	set_prolog_flag(user_error, _Error).
+	open('//python/input', read, Input, []),
+	open('//python/sys.stdout', append, Output, []),
+	open('//python/sys.stdout', append, Error, []),
+	set_prolog_flag(user_input, Input),
+	set_prolog_flag(user_output, Output),
+	set_prolog_flag(user_error, Error).
 
 exit_cell(_Self) :-
 	%close( user_input),
@@ -239,14 +239,21 @@ optype(yf,pos).
 
 :- dynamic syntax_error/4, undo/1.
 
+user:portray_message(_Severity, error(syntax_error(Cause),info(between(_,LN,_), _FileName, CharPos, Details))) :-
+	nb_getval(jupyter_cell, on),
+        assert( syntax_error(Cause,LN,CharPos,Details) ).
+user:portray_message(_Severity, error(style_check(_),_) ) :-
+	nb_getval(jupyter_cell, on).
+      
 open_events(Self, Text, Stream) :-
-    Self.errors := [],
-    open_mem_read_stream( Text, Stream ),
-    assert((user:portray_message(_Severity, error(syntax_error(Cause),info(between(_,LN,_), _FileName, CharPos, Details))) :-
-        assert( syntax_error(Cause,LN,CharPos,Details) )
-        )).
+	Self.errors := [],
+	nb_setval( jupyter, on),
+    open_mem_read_stream( Text, Stream ).
 
+:- initialization( nb_setval( jupyter, off ) ).
+		     
 close_events( _Self ) :-
+	nb_setval( jupyter, off ),
 	retract( undo(G) ),
 	call(G),
 	fail.
@@ -255,3 +262,5 @@ close_events( Self ) :-
     Self.errors := [t(C,L,N,A)] + Self.errors,
     fail.
 close_events( _ ).
+
+:- ( start_low_level_trace ).