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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 _del_thread(self, dwThreadId):
 """ Private method to remove a thread object from the snapshot. @type dwThreadId: int @param dwThreadId: Global thread ID. """

        try:
            aThread = self.__threadDict[dwThreadId]
            del self.__threadDict[dwThreadId]
        except KeyError:
            aThread = None
            msg = "Unknown thread ID %d" % dwThreadId
            warnings.warn(msg, RuntimeWarning)
        if aThread:
            aThread.clear()