wrapped type that inherits after template cant cast to type that template inherits from.

class ISerializable
{
public:
    std::string addToState(std::string& _state, const ISerializable& _value, const std::string& _label = "") const
    { 
        addToString(_state, &_value, _label); 
        return _state; 
    }
};

class ExtBaseUiElement
{
};

template<class Tui, class Tval>
class ExtUiElement : public ExtBaseUiElement, public ISerializable
{
};

class ExtCheckBox
{
};

class ExtCheckBoxBool : public ExtUiElement<ExtCheckBox, bool>
{
};

class GuiChart : public ISerializable
{
};

<object-type name="ISerializable"/>
<object-type name="GuiChart"/>
<object-type name="ExtBaseUiElement"/>
<object-type name="ExtUiElement" generate="no"/>
<object-type name="ExtComboBox" generate="no"/>
<object-type name="ExtUiElement&lt;ExtCheckBox,bool&gt;" generate="no"/>
<object-type name="ExtCheckBoxBool"/>

import AppLib

chart = AppLib.GuiChart()
checkbox = AppLib.ExtCheckBoxBool()

state = ""
state = self.addToState(state, chart , "chart")  # works
state = self.addToState(state, checkbox , "checkbox")  # not working