import os, sys, time
null = open(os.devnull, 'wb')
stdout = sys.stdout
dt = []
for loop in range(10):
    sys.stdout = null
    t0 = time.time()
    for subloop in range(100):
        import this
        this=None
        del sys.modules['this']
    dt.append(time.time() - t0)
    sys.stdout = stdout
print("Best: %.1f ms" % (min(dt)*1000,))