Traceback (most recent call last):
  File "/dist-packages/trytond/protocols/jsonrpc.py", line 108, in _marshaled_dispatch
    response['result'] = dispatch_method(method, params)
  File "/dist-packages/trytond/protocols/jsonrpc.py", line 147, in _dispatch
    res = dispatch(*args)
  File "/dist-packages/trytond/protocols/dispatcher.py", line 155, in dispatch
    res = getattr(obj, method)(*args_without_context, **kargs)
  File "/dist-packages/trytond/model/modelsql.py", line 1119, in delete
    'WHERE ' + red_sql, red_ids)
  File "/dist-packages/trytond/backend/postgresql/database.py", line 319, in execute
    res = self.cursor.execute(sql, params)
IntegrityError: update or delete on table "product_category" violates foreign key constraint "product_template_category_fkey" on table "product_template"
DETAIL:  Key (id)=(10) is still referenced from table "product_template".