<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _add_thread(self, aThread):
 """ Private method to add a thread object to the snapshot. @type aThread: L{Thread} @param aThread: Thread object. """

##        if not isinstance(aThread, Thread):
##            if hasattr(aThread, '__class__'):
##                typename = aThread.__class__.__name__
##            else:
##                typename = str(type(aThread))
##            msg = "Expected Thread, got %s instead" % typename
##            raise TypeError(msg)
        dwThreadId = aThread.dwThreadId
##        if dwThreadId in self.__threadDict:
##            msg = "Already have a Thread object with ID %d" % dwThreadId
##            raise KeyError(msg)
        aThread.set_process(self)
        self.__threadDict[dwThreadId] = aThread