Implement support for waiting for PipeIOServer to stop

echo_server.py

@@ -16,3 +16,4 @@ if __name__ == "__main__":
     print('Running pipe IO server with named pipes:')
     print(f'Input:  {pipe_io.in_pipe}')
     print(f'Output: {pipe_io.out_pipe}')
+    pipe_io.wait()

pipe_io_server/pipe_io_server.py

@@ -58,3 +58,6 @@ class PipeIOServer(ABC, Thread):
                 thread.stop()
         Pipe(self.in_pipe).remove()
         Pipe(self.out_pipe).remove()
+
+    def wait(self):
+        self._stop_event.wait()