exprt wizard begonnen

invoice.py

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+# -*- coding: utf-8 -*-
+# This file is part of the cashbook-module from m-ds for Tryton.
+# The COPYRIGHT file at the top level of this repository contains the
+# full copyright notices and license terms.
+
+from trytond.pool import PoolMeta
+from trytond.pyson import Eval, And, Or
+
+
+class InvoiceLine(metaclass=PoolMeta):
+    __name__ = 'account.invoice.line'
+
+    @classmethod
+    def __setup__(cls):
+        super(InvoiceLine, cls).__setup__()
+        cls.unit.states['required'] = Or(
+            cls.unit.states['required'],
+            And(
+                Eval('type') == 'line',
+                Eval('quantity', None) != None,
+                ),
+            )
+        cls.unit.depends.extend(['type', 'quantity'])
+
+# end Invoice