diff --git a/app/decorators.py b/app/decorators.py
index d1c4745be..866ee8a97 100644
--- a/app/decorators.py
+++ b/app/decorators.py
@@ -41,19 +41,19 @@ class ZRequest(object):
     "Emulating Zope 2 REQUEST"
 
     def __init__(self):
-        self.URL = request.base_url.encode(
-            "utf-8"
-        )  # necessaire pour ScoDoc 8 en Python 2 #sco8
+        self.URL = (
+            request.base_url
+        )  # .encode("utf-8")  # necessaire pour ScoDoc 8 en Python 2 #sco8
         self.URL0 = self.URL
-        self.BASE0 = request.url_root.encode("utf-8")
-        self.QUERY_STRING = request.query_string.encode("utf-8")
-        self.REQUEST_METHOD = request.method.encode("utf-8")
+        self.BASE0 = request.url_root  # .encode("utf-8")
+        self.QUERY_STRING = request.query_string  # .encode("utf-8")
+        self.REQUEST_METHOD = request.method  # .encode("utf-8")
         self.AUTHENTICATED_USER = current_user
         self.REMOTE_ADDR = request.remote_addr
         if request.method == "POST":
-            # self.form = request.form  # xxx encode en utf-8 !
+            self.form = request.form  # xxx encode en utf-8 !
             # Encode en utf-8 pour ScoDoc8 #sco8
-            self.form = {k: v.encode("utf-8") for (k, v) in request.form.items()}
+            # self.form = {k: v.encode("utf-8") for (k, v) in request.form.items()}
             if request.files:
                 # Add files in form: must copy to get a mutable version
                 # request.form is a werkzeug.datastructures.ImmutableMultiDict
@@ -64,8 +64,9 @@ class ZRequest(object):
                 if k.endswith(":list"):
                     self.form[k[:-5]] = request.form.getlist(k)
         elif request.method == "GET":
+            self.form = {k: v for (k, v) in request.args.items()}  # forme python3
             # Encode en utf-8 pour ScoDoc8 #sco8
-            self.form = {k: v.encode("utf-8") for (k, v) in request.args.items()}
+            # self.form = {k: v.encode("utf-8") for (k, v) in request.args.items()}
         self.RESPONSE = ZResponse()
 
     def __str__(self):
@@ -88,7 +89,7 @@ class ZResponse(object):
 
     def redirect(self, url):
         current_app.logger.debug("ZResponse redirect to:" + str(url))
-        return flask.redirect(url.decode("utf-8"))  # http 302 # #sco8 unicode
+        return flask.redirect(url)  # .decode("utf-8"))  # http 302 # #sco8 unicode
 
     def setHeader(self, header, value):
         self.headers[header.lower()] = value
@@ -99,7 +100,7 @@ def permission_required(permission):
         @wraps(f)
         def decorated_function(*args, **kwargs):
             if "scodoc_dept" in kwargs:
-                g.scodoc_dept = kwargs["scodoc_dept"].encode("utf-8")  # sco8
+                g.scodoc_dept = kwargs["scodoc_dept"]  # .encode("utf-8")  # sco8
                 del kwargs["scodoc_dept"]
             # current_app.logger.info(
             #    "permission_required: %s in %s" % (permission, g.scodoc_dept)
@@ -147,7 +148,7 @@ def scodoc7func(context):
                 return func(*args, **kwargs)
             #
             if "scodoc_dept" in kwargs:
-                g.scodoc_dept = kwargs["scodoc_dept"].encode("utf-8")  # sco8
+                g.scodoc_dept = kwargs["scodoc_dept"]  # .encode("utf-8")  # sco8
                 del kwargs["scodoc_dept"]
             elif not hasattr(g, "scodoc_dept"):
                 g.scodoc_dept = None
@@ -159,7 +160,7 @@ def scodoc7func(context):
             req_args = REQUEST.form  # args from query string (get) or form (post)
             # --- Add positional arguments
             pos_arg_values = []
-            # PY3 à remplacer par inspect.getfullargspec en py3:
+            # PY3 à remplacer par inspect.getfullargspec en py3: TODO
             argspec = inspect.getargspec(func)
             current_app.logger.info("argspec=%s" % str(argspec))
             nb_default_args = len(argspec.defaults) if argspec.defaults else 0
@@ -174,10 +175,10 @@ def scodoc7func(context):
                     pos_arg_values.append(context)
                 else:
                     # XXX Convert to regular string for ScoDoc8/Python 2 #py3
-                    if isinstance(req_args[arg_name], str):
-                        pos_arg_values.append(req_args[arg_name].encode("utf-8"))
-                    else:
-                        pos_arg_values.append(req_args[arg_name])
+                    # if isinstance(req_args[arg_name], str):
+                    #    pos_arg_values.append(req_args[arg_name].encode("utf-8"))
+                    # else:
+                    pos_arg_values.append(req_args[arg_name])
             current_app.logger.info("pos_arg_values=%s" % pos_arg_values)
             # Add keyword arguments
             if nb_default_args:
@@ -187,10 +188,10 @@ def scodoc7func(context):
                     elif arg_name in req_args:
                         # set argument kw optionnel
                         # XXX Convert to regular string for ScoDoc8/Python 2 #py3
-                        if isinstance(req_args[arg_name], str):
-                            kwargs[arg_name] = req_args[arg_name].encode("utf-8")
-                        else:
-                            kwargs[arg_name] = req_args[arg_name]
+                        # if isinstance(req_args[arg_name], str):
+                        #    kwargs[arg_name] = req_args[arg_name].encode("utf-8")
+                        # else:
+                        kwargs[arg_name] = req_args[arg_name]
             current_app.logger.info(
                 "scodoc7func_decorator: top_level=%s, pos_arg_values=%s, kwargs=%s"
                 % (top_level, pos_arg_values, kwargs)
diff --git a/app/scodoc/requirements-3.7.txt b/app/scodoc/requirements-3.7.txt
index 6be0fa12f..d78bacc3f 100644
--- a/app/scodoc/requirements-3.7.txt
+++ b/app/scodoc/requirements-3.7.txt
@@ -1,4 +1,5 @@
 alembic==1.6.5
+astroid==2.6.2
 Babel==2.9.1
 blinker==1.4
 certifi==2021.5.30
@@ -22,14 +23,19 @@ html2text==2020.1.16
 icalendar==4.0.7
 idna==2.10
 importlib-metadata==4.6.1
+isort==5.9.2
 itsdangerous==2.0.1
 Jinja2==3.0.1
+lazy-object-proxy==1.6.0
 Mako==1.1.4
 MarkupSafe==2.0.1
+mccabe==0.6.1
 Pillow==8.3.1
 pkg-resources==0.0.0
 psycopg2==2.9.1
 PyJWT==2.1.0
+pylint==2.9.3
+pylint-flask-sqlalchemy==0.2.0
 PyRSS2Gen==1.1
 python-dateutil==2.8.1
 python-dotenv==0.18.0
@@ -39,9 +45,12 @@ reportlab==3.5.68
 requests==2.25.1
 six==1.16.0
 SQLAlchemy==1.4.20
+toml==0.10.2
+typed-ast==1.4.3
 typing-extensions==3.10.0.0
 urllib3==1.26.6
 visitor==0.1.3
 Werkzeug==2.0.1
+wrapt==1.12.1
 WTForms==2.3.3
 zipp==3.5.0
diff --git a/app/scodoc/sco_abs.py b/app/scodoc/sco_abs.py
index beba41554..9464e9897 100644
--- a/app/scodoc/sco_abs.py
+++ b/app/scodoc/sco_abs.py
@@ -1060,7 +1060,7 @@ def invalidateAbsEtudDate(context, etudid, date):
     Invalide cache absence et PDF bulletins si nécessaire.
     date: date au format ISO
     """
-    import sco_compute_moy
+    from app.scodoc import sco_compute_moy
 
     # Semestres a cette date:
     etud = sco_etud.get_etud_info(etudid=etudid, filled=True)[0]
diff --git a/app/scodoc/sco_etud.py b/app/scodoc/sco_etud.py
index 6af51b730..8a4134302 100644
--- a/app/scodoc/sco_etud.py
+++ b/app/scodoc/sco_etud.py
@@ -143,14 +143,7 @@ def format_prenom(s):
     r = []
     for frag in frags:
         fs = frag.split("-")
-        r.append(
-            "-".join(
-                [
-                    x.decode(SCO_ENCODING).lower().capitalize().encode(SCO_ENCODING)
-                    for x in fs
-                ]
-            )
-        )
+        r.append("-".join([x.lower().capitalize() for x in fs]))
     return " ".join(r)
 
 
diff --git a/app/scodoc/sco_formsemestre.py b/app/scodoc/sco_formsemestre.py
index 8acae1ba2..c21c642d2 100644
--- a/app/scodoc/sco_formsemestre.py
+++ b/app/scodoc/sco_formsemestre.py
@@ -128,8 +128,8 @@ def do_formsemestre_list(context, *a, **kw):
 def formsemestre_enrich(context, sem):
     """Ajoute champs souvent utiles: titre + annee et dateord (pour tris)"""
     # imports ici pour eviter refs circulaires
-    import sco_formsemestre_edit
-    import sco_etud
+    from app.scodoc import sco_formsemestre_edit
+    from app.scodoc import sco_etud
     from app.views import notes
 
     F = notes.formation_list(context, args={"formation_id": sem["formation_id"]})[0]
diff --git a/app/scodoc/sco_formsemestre_edit.py b/app/scodoc/sco_formsemestre_edit.py
index 3e8e60425..a35b16319 100644
--- a/app/scodoc/sco_formsemestre_edit.py
+++ b/app/scodoc/sco_formsemestre_edit.py
@@ -1444,7 +1444,7 @@ def do_formsemestre_delete(context, formsemestre_id, REQUEST):
     sco_formsemestre._formsemestreEditor.delete(cnx, formsemestre_id)
 
     # news
-    import sco_news
+    from app.scodoc import sco_news
 
     sco_news.add(
         context,
diff --git a/app/scodoc/sco_utils.py b/app/scodoc/sco_utils.py
index 9e765b1be..637bbf751 100644
--- a/app/scodoc/sco_utils.py
+++ b/app/scodoc/sco_utils.py
@@ -603,14 +603,15 @@ def check_scodoc7_password(scodoc7_hash, password):
 
 
 # Simple string manipulations
-# on utf-8 encoded python strings
-# (yes, we should only use unicode strings, but... we use only strings)
+#    not necessary anymore in Python 3 ! TODO remove
 def strupper(s):
-    return s.decode(SCO_ENCODING).upper().encode(SCO_ENCODING)
+    return s.upper()
+    # return s.decode(SCO_ENCODING).upper().encode(SCO_ENCODING)
 
 
 def strlower(s):
-    return s.decode(SCO_ENCODING).lower().encode(SCO_ENCODING)
+    return s.lower()
+    # return s.decode(SCO_ENCODING).lower().encode(SCO_ENCODING)
 
 
 def strcapitalize(s):
diff --git a/config/scodocutils.py b/config/scodocutils.py
index b099380fb..5b893dcfe 100755
--- a/config/scodocutils.py
+++ b/config/scodocutils.py
@@ -53,7 +53,7 @@ def get_users_cnx_str():
     "db cnx string for users database (used only during upgrades to modify db schema)"
     # uses default in sco_utils
     # For customized installs, define the value here (used only during upgrades)
-    import sco_utils
+    from app.scodoc import sco_utils
 
     return sco_utils.SCO_DEFAULT_SQL_USERS_CNX