Fix

employee.py

@@ -7,8 +7,7 @@ from trytond.transaction import Transaction
 __all__ = ['Employee']
 
 
-class Employee:
-    __metaclass__ = PoolMeta
+class Employee(metaclass=PoolMeta):
     __name__ = 'company.employee'
     active = fields.Boolean('Active')
     code = fields.Char('Code', size=None, select=True)
@@ -32,9 +31,9 @@ class Employee:
     def __setup__(cls):
         super(Employee, cls).__setup__()
         table = cls.__table__()
-        cls._sql_constraints += [
-            ('party_uniq', Unique(table, table.party), 'Employee already exists!'),
-        ]
+        cls._sql_constraints += [(
+            'party_uniq', Unique(table, table.party), 'Employee already exists!'
+        )]
 
     @classmethod
     def __register__(cls, module_name):
@@ -42,14 +41,12 @@ class Employee:
         cursor = Transaction().connection.cursor()
         sql_table = cls.__table__()
 
-        # Migration:
-        # - Rename in_process to aspirant into contracting_state
-
+        # Migration: Rename in_process to aspirant into contracting_state
         cursor.execute(*sql_table.update(
             columns=[sql_table.contracting_state],
             values=['aspirant'],
             where=(sql_table.contracting_state == 'in_process')
-            ))
+        ))
 
     @staticmethod
     def default_active():
@@ -80,4 +77,4 @@ class Employee:
     @fields.depends('contract')
     def on_change_with_salary(self):
         if self.contract:
-           self.salary = self.contract.salary
+            self.salary = self.contract.salary