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有没有办法深度复制包含关联代理的 SQLAlchemy 类的对象实例？

例如，当对此类的实例进行深度复制时

class Device(Base):

    __tablename__ = 'collect_inventory'

    _id = Column('id', Integer, primary_key=True)
    _ip = Column('ip', String(15), index=True)

    fields = association_proxy("field_values", "value",
                               creator=lambda k, v:
                                       FieldValue(field=k, value=v)
                              )

我收到此错误：

  File "/opt/secadvisor/lib/component.py", line 198, in _deliver_mods
    receiver.receive(copy.deepcopy(data), msg_type, module_name, component)
  File "/usr/lib64/python2.6/copy.py", line 189, in deepcopy
    y = _reconstruct(x, rv, 1, memo)
  File "/usr/lib64/python2.6/copy.py", line 338, in _reconstruct
    state = deepcopy(state, memo)
  File "/usr/lib64/python2.6/copy.py", line 162, in deepcopy
    y = copier(x, memo)
  File "/usr/lib64/python2.6/copy.py", line 255, in _deepcopy_dict
    y[deepcopy(key, memo)] = deepcopy(value, memo)
  File "/usr/lib64/python2.6/copy.py", line 162, in deepcopy
    y = copier(x, memo)
  File "/usr/lib64/python2.6/copy.py", line 235, in _deepcopy_tuple
    y.append(deepcopy(a, memo))
  File "/usr/lib64/python2.6/copy.py", line 189, in deepcopy
    y = _reconstruct(x, rv, 1, memo)
  File "/usr/lib64/python2.6/copy.py", line 338, in _reconstruct
    state = deepcopy(state, memo)
  File "/usr/lib64/python2.6/copy.py", line 162, in deepcopy
    y = copier(x, memo)
  File "/usr/lib64/python2.6/copy.py", line 255, in _deepcopy_dict
    y[deepcopy(key, memo)] = deepcopy(value, memo)
  File "/usr/lib64/python2.6/copy.py", line 189, in deepcopy
    y = _reconstruct(x, rv, 1, memo)
  File "/usr/lib64/python2.6/copy.py", line 323, in _reconstruct
    y = callable(*args)
  File "/usr/lib64/python2.6/copy_reg.py", line 93, in __newobj__
    return cls.__new__(cls, *args)
TypeError: attrgetter expected 1 arguments, got 0

fields仅在访问 association_proxy 字段（在本例中）时才会发生错误。

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0 回答 0