gistfile1.py

Traceback (most recent call last):
  File "/trytond/protocols/jsonrpc.py", line 123, in _marshaled_dispatch
    response['result'] = dispatch_method(method, params)
  File "/trytond/protocols/jsonrpc.py", line 156, in _dispatch
    res = dispatch(*args)
  File "/trytond/protocols/dispatcher.py", line 154, in dispatch
    result = rpc.result(meth(*args, **kwargs))
  File "/trytond/wizard/wizard.py", line 259, in execute
    return wizard._execute(state_name)
  File "/trytond/wizard/wizard.py", line 271, in _execute
    view['fields'].keys())
  File "/trytond/wizard/wizard.py", line 87, in get_defaults
    defaults.update(default(fields))
  File "/trytond/modules/purchase/purchase.py", line 1847, in default_ask
    for line in purchase.lines:
  File "/trytond/model/modelstorage.py", line 1137, in __getattr__
    return super(ModelStorage, self).__getattr__(name)
  File "/trytond/model/model.py", line 629, in __getattr__
    % (self.__name__, name, self._values))
AttributeError: 'purchase.purchase' Model has no attribute 'lines': None