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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _read_widget(self):
 """Returns the value currently stored into the widget, after transforming it accordingly to possibly specified function. This is implemented by calling the getter provided by the user. This method can raise InvalidValue (raised by the getter) when the value in the widget must not be considered as valid."""

        getter = self._wid_info[self._wid][0]
        return getter(self._wid)