diff --git a/printer_zpl2/tests/test_generate_action.py b/printer_zpl2/tests/test_generate_action.py
index 194dd87..b9e8450 100644
--- a/printer_zpl2/tests/test_generate_action.py
+++ b/printer_zpl2/tests/test_generate_action.py
@@ -1,3 +1,4 @@
+# Copyright (C) 2018 Florent Mirieu (<https://github.com/fmdl>)
 # License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
 
 from odoo.tests.common import TransactionCase
diff --git a/printer_zpl2/tests/test_printing_label_zpl2.py b/printer_zpl2/tests/test_printing_label_zpl2.py
index 7418382..084b19b 100644
--- a/printer_zpl2/tests/test_printing_label_zpl2.py
+++ b/printer_zpl2/tests/test_printing_label_zpl2.py
@@ -45,13 +45,13 @@ class TestPrintingLabelZpl2(TransactionCase):
 
     def new_label(self, vals=None):
         values = self.label_vals.copy()
-        if vals is not None:
+        if vals:
             values.update(vals)
         return self.Model.create(values)
 
     def new_component(self, vals=None):
         values = self.component_vals.copy()
-        if vals is not None:
+        if vals:
             values.update(vals)
         return self.ComponentModel.create(values)
 
diff --git a/printer_zpl2/tests/test_test_mode.py b/printer_zpl2/tests/test_test_mode.py
index 870a837..8917142 100644
--- a/printer_zpl2/tests/test_test_mode.py
+++ b/printer_zpl2/tests/test_test_mode.py
@@ -1,3 +1,4 @@
+# Copyright (C) 2018 Florent Mirieu (<https://github.com/fmdl>)
 # License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
 import mock
 
diff --git a/printer_zpl2/tests/test_wizard_import_zpl2.py b/printer_zpl2/tests/test_wizard_import_zpl2.py
index ce1a8e3..3360b53 100644
--- a/printer_zpl2/tests/test_wizard_import_zpl2.py
+++ b/printer_zpl2/tests/test_wizard_import_zpl2.py
@@ -1,3 +1,4 @@
+# Copyright (C) 2018 Florent Mirieu (<https://github.com/fmdl>)
 # License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
 
 from odoo.tests.common import TransactionCase
diff --git a/printer_zpl2/views/printing_label_zpl2.xml b/printer_zpl2/views/printing_label_zpl2.xml
index d22cea1..89c6e78 100644
--- a/printer_zpl2/views/printing_label_zpl2.xml
+++ b/printer_zpl2/views/printing_label_zpl2.xml
@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="UTF-8"?>
+<?xml version="1.0"?>
 <!--
     Copyright 2016 SYLEAM
     License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
diff --git a/printer_zpl2/wizard/print_record_label.xml b/printer_zpl2/wizard/print_record_label.xml
index 4f19936..bba539e 100644
--- a/printer_zpl2/wizard/print_record_label.xml
+++ b/printer_zpl2/wizard/print_record_label.xml
@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="UTF-8"?>
+<?xml version="1.0"?>
 <!--
     Copyright 2016 SYLEAM
     License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
diff --git a/printer_zpl2/wizard/wizard_import_zpl2.py b/printer_zpl2/wizard/wizard_import_zpl2.py
index 8e5b8b0..3e89d10 100644
--- a/printer_zpl2/wizard/wizard_import_zpl2.py
+++ b/printer_zpl2/wizard/wizard_import_zpl2.py
@@ -1,3 +1,6 @@
+# Copyright (C) 2018 Florent Mirieu (<https://github.com/fmdl>)
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+
 import logging
 import re
 import base64
@@ -6,7 +9,7 @@ import io
 
 
 from PIL import Image, ImageOps
-from odoo import models, api, fields, _
+from odoo import fields, models, _
 
 _logger = logging.getLogger(__name__)
 
@@ -425,7 +428,7 @@ class WizardImportZPl2(models.TransientModel):
             if field in self.model_fields.keys():
                 field_type = self.model_fields[field].get('type', False)
                 if field_type == 'boolean':
-                    if value == '' or value == zpl2.BOOL_NO:
+                    if not value or value == zpl2.BOOL_NO:
                         value = False
                     else:
                         value = True
diff --git a/printer_zpl2/wizard/wizard_import_zpl2.xml b/printer_zpl2/wizard/wizard_import_zpl2.xml
index b718053..adbdb7e 100644
--- a/printer_zpl2/wizard/wizard_import_zpl2.xml
+++ b/printer_zpl2/wizard/wizard_import_zpl2.xml
@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="UTF-8"?>
+<?xml version="1.0"?>
 <odoo>
     <record id="view_wizard_import_zpl2_form" model="ir.ui.view">
         <field name="name">wizard.import.zpl2.form</field>