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modules/stock_shipment_cost_weight/stock.py

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+# 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 decimal import Decimal
+
+from trytond.pool import Pool, PoolMeta
+
+
+class ShipmentCostMixinWeight:
+    __slots__ = ()
+
+    def _get_allocation_shipment_cost_factors_by_weight(self):
+        pool = Pool()
+        Move = pool.get('stock.move')
+        if getattr(Move, 'internal_weight', None):
+            sum_weight = Decimal(0)
+            weights = {}
+            for move in self.shipment_cost_moves:
+                weight = Decimal(str(move.internal_weight or 0))
+                weights[move.id] = weight
+                sum_weight += weight
+
+            if sum_weight:
+                factors = {}
+                for move in self.shipment_cost_moves:
+                    factors[move.id] = weights[move.id] / sum_weight
+                return factors
+        return self._get_allocation_shipment_cost_factors_by_cost()
+
+
+class ShipmentOut(ShipmentCostMixinWeight, metaclass=PoolMeta):
+    __name__ = 'stock.shipment.out'
+
+
+class ShipmentOutReturn(
+        ShipmentCostMixinWeight, metaclass=PoolMeta):
+    __name__ = 'stock.shipment.out.return'