Minor fix

patch.sql

@@ -3,3 +3,11 @@ ALTER TABLE hotel_channel DROP COLUMN commission;
 ALTER TABLE hotel_channel DROP COLUMN payment_method;
 ALTER TABLE hotel_booking RENAME COLUMN party_seller TO channel;
 UPDATE hotel_folio SET nights_quantity=(departure_date-arrival_date)
+
+
+UPDATE account_statement_line SET source=t.booking FROM (
+  SELECT account_statement_line.id AS lid, 'hotel.booking,' || hfst.booking AS booking
+    FROM account_statement_line
+    INNER JOIN hotel_booking_statement_line_rel AS hfst
+      ON hfst.statement_line=account_statement_line.id) AS t
+    WHERE t.lid=account_statement_line.id;

statement.py

@@ -17,6 +17,13 @@ from trytond.report import Report
 class StatementLine(metaclass=PoolMeta):
     __name__ = 'account.statement.line'
 
+    @classmethod
+    def __setup__(cls):
+        super(StatementLine, cls).__setup__()
+        cls.amount.states = {
+            'readonly': True
+        }
+
     @classmethod
     def _get_source(cls):
         return super(StatementLine, cls)._get_source() + [