diff --git a/__init__.py b/__init__.py
index 812c5ca..7609c0a 100644
--- a/__init__.py
+++ b/__init__.py
@@ -1,20 +1,20 @@
 # This file is part of Tryton.  The COPYRIGHT file at the top level of
 # this repository contains the full copyright notices and license terms.
 from trytond.pool import Pool
-import location
-import configuration
-import room
-import booking
-import operation
-import housekeeping
-import company
-import city
-import party
-import channel
-import product
-import sale
-import service
-import policy
+from . import location
+from . import configuration
+from . import room
+from . import booking
+from . import operation
+from . import housekeeping
+from . import company
+from . import city
+from . import party
+from . import channel
+from . import product
+from . import sale
+from . import service
+from . import policy
 
 
 def register():
diff --git a/booking.py b/booking.py
index 64d449d..4209459 100644
--- a/booking.py
+++ b/booking.py
@@ -10,15 +10,8 @@ from trytond.report import Report
 from trytond.pyson import Eval, If, In, Get, Not, Or, Equal, Bool
 from trytond.transaction import Transaction
 from trytond.pool import Pool
-
-
-__all__ = [
-    'Booking', 'BookingLine', 'BookingReport', 'SelectRooms', 'SelectRoomsAsk',
-    'BookingVoucher', 'RoomsOccupancy', 'RoomsOccupancyStart',
-    'RoomsOccupancyReport', 'GuestsListReport', 'GuestsListStart',
-    'RegistrationCardReport', 'BookingForecastReport', 'GuestsList',
-    'Guest', 'BookingDailyStart', 'BookingDaily', 'BookingDailyReport'
-]
+from trytond.model.exceptions import AccessError
+from trytond.i18n import gettext
 
 STATE = [
     (None, ''),
@@ -283,19 +276,6 @@ class Booking(Workflow, ModelSQL, ModelView):
                 'invisible': Eval('state') != 'confirmed'
             },
         })
-        cls._error_messages.update({
-            'invalid_number_principal_guest': ('Must exist one principal guest'),
-            'payterm_missing': ('The payment term is missing!'),
-            'check_time_not_configured': ('The check out time is not configured!'),
-            'invalid_arrival_date': ('You cannot check in before the reserved date!'),
-            'missing_main_guest': ('Missing main guest in lines!'),
-            'missing_select_room': ('Missing select room!'),
-            'missing_default_configuration': ('Missing default configuration sequence!'),
-            'payterm_missing': ('The payment term is missing!'),
-            'room_no_clean': ('The room %s is not clean!'),
-            'missing_sequence_registration': ('Missing the configuration of \
-                registration card sequence!'),
-        })
 
     @classmethod
     def trigger_create(cls, records):
@@ -483,14 +463,13 @@ class Booking(Workflow, ModelSQL, ModelView):
         Fill the number field with the booking sequence
         """
         pool = Pool()
-        Sequence = pool.get('ir.sequence')
         Config = pool.get('hotel.configuration')
         config = Config.get_configuration()
 
         for booking in bookings:
             if booking.number or not config.booking_sequence:
                 continue
-            number = Sequence.get_id(config.booking_sequence.id)
+            number = config.booking_sequence.get()
             cls.write([booking], {'number': number})
 
     def cancel_occupancy(self):
@@ -505,7 +484,6 @@ class Booking(Workflow, ModelSQL, ModelView):
         Fill the number field for registration card with sequence
         """
         pool = Pool()
-        Sequence = pool.get('ir.sequence')
         Config = pool.get('hotel.configuration')
         config = Config.get_configuration()
 
@@ -513,8 +491,8 @@ class Booking(Workflow, ModelSQL, ModelView):
             if booking.registration_card:
                 continue
             if not config.registration_card_sequence:
-                cls.raise_user_error('missing_sequence_registration')
-            number = Sequence.get_id(config.registration_card_sequence.id)
+                raise AccessError(gettext('hotel.msg_missing_sequence_registration'))
+            number = config.registration_card_sequence.get()
             cls.write([booking], {'registration_card': number})
 
     def delete_occupancy(self):
@@ -530,7 +508,7 @@ class Booking(Workflow, ModelSQL, ModelView):
 
         config = Config.get_configuration()
         if config.check_out_time is None or config.check_in_time is None:
-            self.raise_user_error('check_time_not_configured')
+            raise AccessError(gettext('hotel.msg_check_time_not_configured'))
 
         if self.invoice_method == 'by_booking':
             to_create = [(self.party, l, l.product.id, l.unit_price) for l in self.lines]
@@ -558,7 +536,7 @@ class Booking(Workflow, ModelSQL, ModelView):
         ])
         for hk in housekeepings:
             if hk.room.id in rooms_ids:
-                self.raise_user_error('room_no_clean', hk.room.name)
+                raise AccessError(gettext('hotel.msg_room_no_clean', s=hk.room.name))
 
     def get_context_price(self, product):
         context = {}
@@ -697,7 +675,7 @@ class Booking(Workflow, ModelSQL, ModelView):
             self.get_message('El usuario no tiene un correo asociado.')
 
     def get_message(self, message):
-        self.raise_user_error(message)
+        raise AccessError(gettext('hotel.msg_error', s=message))
 
 
 class BookingLine(ModelSQL, ModelView):
@@ -755,17 +733,6 @@ class BookingLine(ModelSQL, ModelView):
             'nationality', 'origin_country', 'target_country',
             'registration_state', 'guests'
         ],
-        cls._error_messages.update({
-            'invalid_number_guests': ('Invalid number of guests for '
-                                      'the room %s.'),
-            'accommodation_not_defined': ('The room %s has not accommodation'),
-            'invalid_date': ('Departure date must be greater \
-                             that arrival date'),
-            'occupied_room': ('The room is occupied in the date %s'),
-            'restring_room': ('The room %s is in restring access for quarantine protocolo!'),
-            'missing_confirm_booking': ('Missing Confirm Booking'),
-            'reservation_checkin': ('The reservation already has check_in or check_out'),
-        })
         cls._buttons.update({
             'check_in': {
                 'invisible': Eval('state') == 'confirmed' and
@@ -835,11 +802,11 @@ class BookingLine(ModelSQL, ModelView):
         Booking.set_registration_card_number([record])
         line = records[0]
         if line.state == 'offer':
-            line.raise_user_error('missing_confirm_booking')
+            raise AccessError(gettext('hotel.msg_missing_confirm_booking'))
         if line.main_guest is None:
-            Booking.raise_user_error('missing_main_guest')
+            raise AccessError(gettext('hotel.msg_missing_main_guest'))
         if line.room is None:
-            Booking.raise_user_error('missing_select_room')
+            raise AccessError(gettext('hotel.msg_missing_select_room'))
         record.check_rooms()
         cls.write([records[0]], {'registration_state': 'check_in'})
         record.update_occupancy(state='open',records=records,check=check)
@@ -953,11 +920,11 @@ class BookingLine(ModelSQL, ModelView):
         """
         Date = Pool().get('ir.date')
         if self.registration_state in (['check_in', 'check_out']):
-            self.raise_user_error('reservation_checkin')
+            raise AccessError(gettext('hotel.msg_reservation_checkin'))
         if self.arrival_date < Date.today():
-            self.raise_user_error('invalid_arrival_date')
+            raise AccessError(gettext('hotel.msg_invalid_arrival_date'))
         if self.arrival_date >= self.departure_date:
-            self.raise_user_error('invalid_date')
+            raise AccessError(gettext('hotel.msg_invalid_date'))
         Operation = Pool().get('hotel.operation')
         operations = Operation.search([
             ('room', '=', self.room.id),
@@ -973,7 +940,7 @@ class BookingLine(ModelSQL, ModelView):
             ])
         print(operations)
         if operations:
-            self.raise_user_error('occupied_room', self.departure_date)
+            raise AccessError(gettext('hotel.msg_occupied_room', s=self.departure_date))
         config = Pool().get('hotel.configuration')(1)
         quarantine_days = config.quarantine_rooms
         room_id = self.room.id
@@ -992,7 +959,7 @@ class BookingLine(ModelSQL, ModelView):
                     ]]]])
             print(operations)
             if operations:
-                self.raise_user_error('restring_room', self.room.name)
+                raise AccessError(gettext('hotel.msg_restring_room', s=self.room.name))
 
     def get_state(self, name):
         if self.booking:
@@ -1044,8 +1011,8 @@ class BookingReport(Report):
     __name__ = 'hotel.booking'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(BookingReport, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         user = Pool().get('res.user')(Transaction().user)
         report_context['company'] = user.company
         return report_context
@@ -1378,8 +1345,8 @@ class BookingForecastReport(Report):
     __name__ = 'hotel.booking_forecast.report'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(BookingForecastReport, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         MAX_DAYS = 30
         pool = Pool()
         Company = pool.get('company.company')
@@ -1444,8 +1411,8 @@ class RegistrationCardReport(Report):
     __name__ = 'hotel.occupancy.registration_card'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(RegistrationCardReport, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         user = Pool().get('res.user')(Transaction().user)
         report_context['company'] = user.company
         return report_context
@@ -1493,8 +1460,8 @@ class GuestsListReport(Report):
     __name__ = 'hotel.guests_list.report'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(GuestsListReport, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         pool = Pool()
         Company = pool.get('company.company')
         Operation = pool.get('hotel.operation')
@@ -1574,8 +1541,8 @@ class RoomsOccupancyReport(Report):
     __name__ = 'hotel.rooms_occupancy.report'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(RoomsOccupancyReport, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         pool = Pool()
         Company = pool.get('company.company')
         Room = pool.get('hotel.room')
@@ -1677,8 +1644,8 @@ class BookingDailyReport(Report):
     __name__ = 'hotel.booking_daily.report'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(BookingDailyReport, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         pool = Pool()
         Company = pool.get('company.company')
         records = BookingLine.search([
diff --git a/company.py b/company.py
index 4fc7e9e..2a894f4 100644
--- a/company.py
+++ b/company.py
@@ -3,8 +3,6 @@
 from trytond.model import fields
 from trytond.pool import PoolMeta
 
-__all__ = ['Company']
-
 
 class Company(metaclass=PoolMeta):
     __name__ = 'company.company'
diff --git a/configuration.py b/configuration.py
index fc47c38..7f93541 100644
--- a/configuration.py
+++ b/configuration.py
@@ -3,8 +3,8 @@
 from trytond.model import ModelView, ModelSQL, fields
 from trytond.pyson import Eval, If
 from trytond.transaction import Transaction
-
-__all__ = ['Configuration', 'ConfigurationProduct']
+from trytond.model.exceptions import AccessError
+from trytond.i18n import gettext
 
 
 class Configuration(ModelSQL, ModelView):
@@ -61,9 +61,6 @@ class Configuration(ModelSQL, ModelView):
     @classmethod
     def __setup__(cls):
         super(Configuration, cls).__setup__()
-        cls._error_messages.update({
-            'missing_default_configuration': ('Missing default configuration sequence!'),
-        })
 
     @staticmethod
     def default_company():
@@ -77,7 +74,7 @@ class Configuration(ModelSQL, ModelView):
                 ('company', '=', company_id)
             ])
             if not config or not config.booking_sequence:
-                cls.raise_user_error('missing_default_configuration')
+                raise AccessError(gettext('hotel.missing_default_configuration'))
             return config
 
 
diff --git a/exceptions.py b/exceptions.py
new file mode 100644
index 0000000..20f4831
--- /dev/null
+++ b/exceptions.py
@@ -0,0 +1,9 @@
+# This file is part of Tryton.  The COPYRIGHT file at the top level of
+# this repository contains the full copyright notices and license terms.
+
+from trytond.exceptions import UserError, UserWarning
+# from trytond.model.exceptions import ValidationError
+
+
+class BadOperationError(UserError):
+    pass
diff --git a/housekeeping.py b/housekeeping.py
index 073e80d..a462f81 100644
--- a/housekeeping.py
+++ b/housekeeping.py
@@ -8,12 +8,6 @@ from trytond.transaction import Transaction
 from datetime import datetime
 from trytond.pool import Pool
 
-__all__ = [
-    'Housekeeping', 'HotelTask', 'HotelHousekeepingTask',
-    'HousekeepingServiceReport', 'HousekeepingService',
-    'HousekeepingServiceStart', 'HousekeepingCleaningType'
-]
-
 STATES = {'invisible': (Eval('type') != 'service')}
 
 
@@ -231,8 +225,8 @@ class HousekeepingServiceReport(Report):
     __name__ = 'hotel.print_housekeeping_service.report'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(HousekeepingServiceReport, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         pool = Pool()
         Company = pool.get('company.company')
         Housekeeping = pool.get('hotel.housekeeping')
diff --git a/location.py b/location.py
index 92d0050..3c22524 100644
--- a/location.py
+++ b/location.py
@@ -2,8 +2,6 @@
 # this repository contains the full copyright notices and license terms.
 from trytond.model import ModelView, ModelSQL, fields
 
-__all__ = ['HotelLocation']
-
 
 class HotelLocation(ModelSQL, ModelView):
     "Hotel Location"
diff --git a/message.xml b/message.xml
new file mode 100644
index 0000000..1eb1384
--- /dev/null
+++ b/message.xml
@@ -0,0 +1,88 @@
+<?xml version="1.0"?>
+<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of
+this repository contains the full copyright notices and license terms. -->
+<tryton>
+    <data grouped="1">
+        <record model="ir.message" id="msg_sale_closed">
+            <field name="text">You can not add charges to a sale is closed %s</field>
+        </record>
+        <record model="ir.message" id="msg_room_not_occupied">
+            <field name="text">The room %s selected is not occupied</field>
+        </record>
+        <record model="ir.message" id="msg_invalid_number_principal_guest">
+            <field name="text">Must exist one principal guest</field>
+        </record>
+        <record model="ir.message" id="msg_payterm_missing">
+            <field name="text">The payment term is missing!</field>
+        </record>
+        <record model="ir.message" id="msg_check_time_not_configured">
+            <field name="text">The check out time is not configured!</field>
+        </record>
+        <record model="ir.message" id="msg_invalid_arrival_date">
+            <field name="text">You cannot check in before the reserved date!</field>
+        </record>
+        <record model="ir.message" id="msg_missing_main_guest">
+            <field name="text">Missing main guest in lines!</field>
+        </record>
+        <record model="ir.message" id="msg_missing_select_room">
+            <field name="text">Missing select room!</field>
+        </record>
+        <record model="ir.message" id="msg_missing_default_configuration">
+            <field name="text">Missing default configuration sequence!</field>
+        </record>
+        <record model="ir.message" id="msg_payterm_missing">
+            <field name="text">The payment term is missing!</field>
+        </record>
+        <record model="ir.message" id="msg_room_no_clean">
+            <field name="text">The room %s is not clean!</field>
+        </record>
+        <record model="ir.message" id="msg_missing_sequence_registration">
+            <field name="text">Missing the configuration of registration card sequence!</field>
+        </record>
+        <record model="ir.message" id="msg_invalid_number_guests">
+            <field name="text">Invalid number of guests for the room %s.</field>
+        </record>
+        <record model="ir.message" id="msg_accommodation_not_defined">
+            <field name="text">The room %s has not accommodation</field>
+        </record>
+        <record model="ir.message" id="msg_invalid_date">
+            <field name="text">Departure date must be greater that arrival date</field>
+        </record>
+        <record model="ir.message" id="msg_occupied_room">
+            <field name="text">The room is occupied in the date %s</field>
+        </record>
+        <record model="ir.message" id="msg_restring_room">
+            <field name="text">The room %s is in restring access for quarantine protocolo!</field>
+        </record>
+        <record model="ir.message" id="msg_missing_confirm_booking">
+            <field name="text">Missing Confirm Booking</field>
+        </record>
+        <record model="ir.message" id="msg_reservation_checkin">
+            <field name="text">The reservation already has check_in or check_out</field>
+        </record>
+        <record model="ir.message" id="msg_error">
+            <field name="text">Error "\n" %s</field>
+        </record>
+        <record model="ir.message" id="msg_missing_default_configuration">
+            <field name="text">Missing default configuration sequence!</field>
+        </record>
+        <record model="ir.message" id="msg_overlap_operation_line">
+            <field name="text">The operation for the room %s</field>
+        </record>
+        <record model="ir.message" id="msg_overlap_operation_line">
+            <field name="text">The operation for the room %s overlaps with another operation!</field>
+        </record>
+        <record model="ir.message" id="msg_invalid_date_range">
+            <field name="text">The start date is greater than end date</field>
+        </record>
+        <record model="ir.message" id="msg_missing_default_configuration">
+            <field name="text">Missing default configuration for check-in time or check-out time!</field>
+        </record>
+        <record model="ir.message" id="msg_occupied_room">
+            <field name="text">The room is occupied %s</field>
+        </record>
+        <record model="ir.message" id="msg_operation_current">
+            <field name="text">Error, Can not select current operation</field>
+        </record>
+    </data>
+</tryton>
diff --git a/operation.py b/operation.py
index 68a736c..48bd921 100644
--- a/operation.py
+++ b/operation.py
@@ -9,16 +9,8 @@ from trytond.pool import Pool
 from trytond.report import Report
 from trytond.wizard import Wizard, StateView, StateAction, Button, StateTransition
 from trytond.transaction import Transaction
-
-__all__ = [
-    'Operation', 'OperationLine', 'OperationMaintenance', 'Migration',
-    'OpenMigration', 'OpenMigrationStart', 'OperationGuest', 'OperationReport',
-    'CheckOutOperation', 'CheckOutOperationFailed', 'ChangeRoomStart',
-    'ChangeRoom', 'TransferOperationStart', 'TransferOperation',
-    'TransferChargeStart', 'TransferCharge', 'OperationByConsumerReport',
-    'OperationBill', 'OperationVoucher', 'StatisticsByMonthStart',
-    'StatisticsByMonth', 'StatisticsByMonthReport'
-]
+from trytond.model.exceptions import AccessError
+from trytond.i18n import gettext
 
 STATES_OP = {
     'readonly': Eval('state').in_(['check_out', 'done', 'cancelled'])
@@ -140,14 +132,6 @@ class Operation(Workflow, ModelSQL, ModelView):
     @classmethod
     def __setup__(cls):
         super(Operation, cls).__setup__()
-        cls._error_messages.update({
-            'overlap_operation_line': ('The operation for the room %s '
-            'overlaps with another operation!'),
-            'invalid_date_range': ('The start date is greater than end date'),
-            'missing_default_configuration': ('Missing default configuration for check-in '
-                'time or check-out time!'),
-            'occupied_room': ('The room is occupied %s')
-        })
         cls._transitions |= set((
             ('draft', 'open'),
             ('draft', 'cancelled'),
@@ -195,7 +179,7 @@ class Operation(Workflow, ModelSQL, ModelView):
                 ]
             ]]])
             if operations:
-                cls.raise_user_error('occupied_room', r.room.name)
+                raise AccessError(gettext('hotel.msg_occupied_room', s=r.room.name))
 
     @classmethod
     def occupancy_rate(cls, start, end):
@@ -367,7 +351,7 @@ class Operation(Workflow, ModelSQL, ModelView):
         config = Configuration.get_configuration()
         if not config.cleaning_check_in or not config.cleaning_check_out \
             or not config.cleaning_occupied:
-            self.raise_user_error('missing_cleaning_configuration')
+            raise AccessError(gettext('hotel.msg_missing_cleaning_configuration'))
         if state == 'check_in':
             values = {
                 'availability': 'occupied',
@@ -384,7 +368,7 @@ class Operation(Workflow, ModelSQL, ModelView):
             ('room', '=', self.room.id)
         ])
         if not housekeepings:
-            self.raise_user_error('missing_configuration_housekeeping_rooms')
+            raise AccessError(gettext('hotel.msg_missing_configuration_housekeeping_rooms'))
         Housekeeping.write(housekeepings, values)
 
     # def get_sale(self, name=None):
@@ -491,7 +475,7 @@ class Operation(Workflow, ModelSQL, ModelView):
         """
 
         if start_date >= end_date:
-            cls.raise_user_error('invalid_date_range')
+            raise AccessError(gettext('hotel.msg_invalid_date_range'))
 
         # define the domain of the operations that find a
         # room to be available
@@ -529,7 +513,7 @@ class Operation(Workflow, ModelSQL, ModelView):
             start_date, end_date, rooms_ids, operation
         )
         if room.id not in available_rooms:
-            cls.raise_user_error('overlap_operation_line', (room.name,))
+            raise AccessError(gettext('hotel.overlap_operation_line', s=room.name))
 
     def get_nights_quantity(self, name=None):
         """
@@ -1051,8 +1035,8 @@ class Migration(Report):
     __name__ = 'hotel.migration'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(Migration, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         Line = Pool().get('hotel.booking.line')
         start = data['start_date']
         end = data['end_date']
@@ -1067,8 +1051,8 @@ class OperationReport(Report):
     __name__ = 'hotel.operation'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(OperationReport, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         user = Pool().get('res.user')(Transaction().user)
         report_context['company'] = user.company
         return report_context
@@ -1237,9 +1221,6 @@ class TransferOperation(Wizard):
     @classmethod
     def __setup__(cls):
         super(TransferOperation, cls).__setup__()
-        cls._error_messages.update({
-            'operation_current': ('Error, Can not select current operation'),
-            })
 
     def transition_transfer(self):
         pool = Pool()
@@ -1248,7 +1229,7 @@ class TransferOperation(Wizard):
         current_op = Operation(Transaction().context.get('active_id'))
         target_op = self.start.operation
         if target_op.id == current_op.id:
-            self.raise_user_error('operation_current')
+            raise AccessError(gettext('hotel.msg_operation_current'))
 
         lines_to_transfer = []
         if self.start.tranfer_charges:
@@ -1303,8 +1284,8 @@ class OperationByConsumerReport(Report):
     __name__ = 'hotel.operation.line'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(OperationByConsumerReport, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         pool = Pool()
         Operation = pool.get('hotel.operation')
         user = pool.get('res.user')(Transaction().user)
@@ -1395,8 +1376,8 @@ class StatisticsByMonthReport(Report):
     __name__ = 'hotel.statistics_by_month.report'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(StatisticsByMonthReport, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         Operation = Pool().get('hotel.operation')
         Period = Pool().get('account.period')
         Company = Pool().get('company.company')
diff --git a/party.py b/party.py
index 0c9cd0c..5ab9422 100644
--- a/party.py
+++ b/party.py
@@ -3,12 +3,10 @@
 #and license terms.
 from trytond.pool import PoolMeta, Pool
 from trytond.model import fields, ModelView
-from trytond.wizard import Wizard, StateView, Button, StateTransition, StateReport
+from trytond.wizard import Wizard, StateView, Button, StateTransition
 from trytond.transaction import Transaction
-
-
-__all__ = ['Party', 'CreateGuest', 'CreateGuestStart']
-
+from trytond.model.exceptions import AccessError
+from trytond.i18n import gettext
 
 TYPE = [
     ('', ''),
@@ -169,4 +167,4 @@ class CreateGuest(Wizard):
         return 'end'
 
     def get_message(self, message):
-        self.raise_user_error(message)
+        raise AccessError(gettext('hotel.msg_error', s=message))
diff --git a/policy.py b/policy.py
index 66e3705..e695bbf 100644
--- a/policy.py
+++ b/policy.py
@@ -2,8 +2,6 @@
 # this repository contains the full copyright notices and license terms.
 from trytond.model import ModelView, ModelSQL, fields
 
-__all__ = ['HotelPolicyCancellation']
-
 
 class HotelPolicyCancellation(ModelSQL, ModelView):
     'Hotel Policy Cancellation'
diff --git a/product.py b/product.py
index f4d1110..fbc2dc0 100755
--- a/product.py
+++ b/product.py
@@ -5,8 +5,6 @@ from trytond.model import fields
 from trytond.pool import PoolMeta
 from trytond.pyson import Eval
 
-__all__ = ['Template']
-
 
 KIND = [
     ('', ''),
diff --git a/room.py b/room.py
index a672b75..a11f85b 100644
--- a/room.py
+++ b/room.py
@@ -3,7 +3,6 @@
 from trytond.model import ModelView, ModelSQL, fields
 from trytond.pyson import Eval
 
-__all__ = ['Room', 'Amenities', 'RoomClassification', 'RoomAmenities', 'RoomTemplate']
 
 STATES = {'readonly': (Eval('state') != 'draft')}
 
diff --git a/sale.py b/sale.py
index d94e541..6189c77 100644
--- a/sale.py
+++ b/sale.py
@@ -8,9 +8,6 @@ from trytond.report import Report
 from trytond.model import ModelView, fields
 from trytond.transaction import Transaction
 
-__all__ = ['InvoiceIncomeDaily', 'InvoiceIncomeDailyStart',
-    'InvoiceIncomeDailyReport', 'InvoiceSimplifiedReport']
-
 _ZERO = Decimal(0)
 
 
@@ -61,8 +58,8 @@ class InvoiceIncomeDailyReport(Report):
     __name__ = 'hotel.invoice_income_daily_report'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(InvoiceIncomeDailyReport, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         pool = Pool()
         Invoice = pool.get('account.invoice')
         Company = pool.get('company.company')
@@ -197,8 +194,8 @@ class InvoiceSimplifiedReport(Report):
     __name__ = 'account.invoice_simplified'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(InvoiceSimplifiedReport, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         Company = Pool().get('company.company')
 
         categories = {}
diff --git a/service.py b/service.py
index 9a8132e..18378f0 100644
--- a/service.py
+++ b/service.py
@@ -7,9 +7,8 @@ from trytond.pyson import Eval
 from trytond.modules.company import CompanyReport
 from trytond.wizard import Wizard, StateView, Button, StateTransition
 from trytond.transaction import Transaction
-
-__all__ = ['Service', 'ServiceLine', 'ServiceReport', 'ServiceKind',
-    'CreateDailyServices', 'CreateDailyServicesStart']
+from trytond.model.exceptions import AccessError
+from trytond.i18n import gettext
 
 STATES = {
     'readonly': Eval('state') == 'checked'
@@ -18,6 +17,7 @@ STATES_LINE = {
     'readonly': Eval('state') == 'loaded'
 }
 
+
 class ServiceKind(ModelSQL, ModelView):
     'Service Kind'
     __name__ = 'hotel.service.kind'
@@ -184,10 +184,6 @@ class ServiceLine(Workflow, ModelSQL, ModelView):
                 'invisible': Eval('state') != 'draft',
             },
         })
-        cls._error_messages.update({
-            'sale_closed': ('You can not add charges to a sale is closed %s'),
-            'room_not_occupied': ('The room %s selected is not occupied'),
-        })
 
     @staticmethod
     def default_quantity():
@@ -288,8 +284,8 @@ class ServiceReport(CompanyReport):
     __name__ = 'hotel.service'
 
     @classmethod
-    def get_context(cls, records, data):
-        report_context = super(ServiceReport, cls).get_context(records, data)
+    def get_context(cls, records, header, data):
+        report_context = super().get_context(records, header, data)
         return report_context
 
 
diff --git a/tryton.cfg b/tryton.cfg
index 8fe01f4..3d78746 100644
--- a/tryton.cfg
+++ b/tryton.cfg
@@ -1,5 +1,5 @@
 [tryton]
-version=5.0.4
+version=6.0.0
 depends:
     party
     company