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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 async_get(self, handle):
        ''' Blocks until the thread created by async_run returns '''
        assert handle in self._thread_pool, 'Invalid async call handle'
        result = self._thread_pool[handle].result_queue.get()
        del self._thread_pool[handle]
        return result