Fix flake8 errors and warnings

We add the flake8 configuration used so we ensure everyone uses the same.
We remove the usage of __all__ for non public API.
When possible, we rationalize the class name according to its __name__ and module.

issue9082
review297061002

.flake8

@@ -0,0 +1,2 @@
+[flake8]
+ignore=E123,E124,E126,E128,W503

__init__.py

@@ -2,25 +2,25 @@
 # this repository contains the full copyright notices and license terms.
 
 from trytond.pool import Pool
-from .dunning import *
-from .party import *
-from .account import *
+from . import dunning
+from . import party
+from . import account
 
 
 def register():
     Pool.register(
-        Procedure,
-        Level,
-        Dunning,
-        CreateDunningStart,
-        ProcessDunningStart,
-        Party,
-        PartyDunningProcedure,
-        Configuration,
-        ConfigurationDefaultDunningProcedure,
-        MoveLine,
+        dunning.Procedure,
+        dunning.Level,
+        dunning.Dunning,
+        dunning.CreateDunningStart,
+        dunning.ProcessDunningStart,
+        party.Party,
+        party.PartyDunningProcedure,
+        account.Configuration,
+        account.ConfigurationDefaultDunningProcedure,
+        account.MoveLine,
         module='account_dunning', type_='model')
     Pool.register(
-        CreateDunning,
-        ProcessDunning,
+        dunning.CreateDunning,
+        dunning.ProcessDunning,
         module='account_dunning', type_='wizard')

account.py

@@ -3,8 +3,6 @@
 from trytond.pool import PoolMeta
 from trytond.model import ModelSQL, ValueMixin, fields
 
-
-__all__ = ['Configuration', 'ConfigurationDefaultDunningProcedure', 'MoveLine']
 default_dunning_procedure = fields.Many2One(
     'account.dunning.procedure', "Default Dunning Procedure",
     help="The default dunning procedure for new customers.")

dunning.py

@@ -13,10 +13,6 @@ from trytond.wizard import Wizard, StateView, StateAction, StateTransition, \
     Button
 from trytond.pool import Pool
 
-__all__ = ['Procedure', 'Level', 'Dunning',
-    'CreateDunningStart', 'CreateDunning',
-    'ProcessDunningStart', 'ProcessDunning']
-
 
 class Procedure(ModelSQL, ModelView):
     'Account Dunning Procedure'
@@ -67,6 +63,7 @@ class Level(sequence_ordered(), ModelSQL, ModelView):
         if self.overdue is not None:
             return (date - line.maturity_date) >= self.overdue
 
+
 _STATES = {
     'readonly': Eval('state') != 'draft',
     }

party.py

@@ -5,7 +5,6 @@ from trytond.model import ModelSQL, ValueMixin, fields
 from trytond.pool import PoolMeta, Pool
 from trytond.tools.multivalue import migrate_property
 
-__all__ = ['Party', 'PartyDunningProcedure']
 dunning_procedure = fields.Many2One(
     'account.dunning.procedure', "Dunning Procedure")
 

setup.py

@@ -79,8 +79,8 @@ setup(name=name,
     keywords='tryton account dunning',
     package_dir={'trytond.modules.account_dunning': '.'},
     packages=(
-        ['trytond.modules.account_dunning'] +
-        ['trytond.modules.account_dunning.%s' % p for p in find_packages()]
+        ['trytond.modules.account_dunning']
+        + ['trytond.modules.account_dunning.%s' % p for p in find_packages()]
         ),
     package_data={
         'trytond.modules.account_dunning': (info.get('xml', [])
@@ -93,7 +93,8 @@ setup(name=name,
         'Intended Audience :: Developers',
         'Intended Audience :: Financial and Insurance Industry',
         'Intended Audience :: Legal Industry',
-        'License :: OSI Approved :: GNU General Public License v3 or later (GPLv3+)',
+        'License :: OSI Approved :: '
+        'GNU General Public License v3 or later (GPLv3+)',
         'Natural Language :: Bulgarian',
         'Natural Language :: Catalan',
         'Natural Language :: Chinese (Simplified)',

tests/__init__.py

@@ -2,7 +2,7 @@
 # this repository contains the full copyright notices and license terms.
 
 try:
-    from trytond.modules.account_dunning.tests.test_account_dunning import suite
+    from trytond.modules.account_dunning.tests.test_account_dunning import suite  # noqa: E501
 except ImportError:
     from .test_account_dunning import suite