Migrate to python 3.

commission.py

@@ -4,8 +4,7 @@
 from trytond.pool import PoolMeta
 __all__ = ['Commission']
 
-class Commission:
-    __metaclass__ = PoolMeta
+class Commission(metaclass=PoolMeta):
     __name__ = 'commission'
 
     @classmethod

invoice.py

@@ -11,8 +11,7 @@ __all__ = ['Invoice']
 ZERO = Decimal('0.0')
 
 
-class Invoice:
-    __metaclass__ = PoolMeta
+class Invoice(metaclass=PoolMeta):
     __name__ = 'account.invoice'
     payment_type_kind = fields.Function(fields.Selection(KINDS,
             'Kind of payment type',

move.py

@@ -9,8 +9,7 @@ from trytond.transaction import Transaction
 __all__ = ['Move', 'Line']
 
 
-class Move:
-    __metaclass__ = PoolMeta
+class Move(metaclass=PoolMeta):
     __name__ = 'account.move'
 
     def cancel(self, default=None):
@@ -18,8 +17,7 @@ class Move:
             return super(Move, self).cancel(default=default)
 
 
-class Line:
-    __metaclass__ = PoolMeta
+class Line(metaclass=PoolMeta):
     __name__ = 'account.move.line'
 
     account_kind = fields.Function(fields.Selection([

party.py

@@ -27,8 +27,7 @@ class PartyAccountPaymentType(CompanyValueMixin, ModelSQL):
     supplier_payment_type = supplier_payment_type
 
 
-class Party:
-    __metaclass__ = PoolMeta
+class Party(metaclass=PoolMeta):
     __name__ = 'party.party'
 
     customer_payment_type = fields.MultiValue(customer_payment_type)

setup.py

@@ -7,10 +7,7 @@ from setuptools import setup
 import re
 import os
 import io
-try:
-    from configparser import ConfigParser
-except ImportError:
-    from ConfigParser import ConfigParser
+from configparser import ConfigParser
 
 MODULE = 'account_payment_type'
 PREFIX = 'trytonspain'

work.py

@@ -6,8 +6,7 @@ from trytond.pool import PoolMeta
 __all__ = ['Work']
 
 
-class Work:
-    __metaclass__ = PoolMeta
+class Work(metaclass=PoolMeta):
     __name__ = 'project.work'
 
     def _get_invoice(self):