[PyQt] RuntimeError: underlying C/C++ object has been deleted

[Alexandr N Zamaraev]

Looks like I got very simplified code.
The real hierarchy for the Data and Model looks like this (may be more 
levels):
[code]
class BaseData(QObject):
   def __init__(self):
     super(BaseData, self).__init__()
     ...
class FinalData(BaseData):
   ...

class BaseModel(QAbstractItemModel):
   def __init__(self, parent, data, ...):
     super(Model, self).__init__(parent)
     ...

class Model(BaseModel):
   ...
[/code]
All my base classes call base constructor directly or through super.
And all the derived classes have no constructor or call it through super.