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+```python
+def worker(x):
+    __import__('time').sleep(1)
+    print(x, end=' ')
+    return x ** 3
+
+with __import__('concurrent').futures.ThreadPoolExecutor(64) as T:
+    y = list(T.map(worker, range(100)))
+# 64개 worker로 100개의 1초 소요되는 작업: 2초후 종료
+
+# x는 순서대로 호출 안되지만 y는 순서대로 나옴
+print(y)
+```
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