语法错误：%time泡菜。倾倒

Question

有人能给我解释一下%时间是怎么工作的吗？ 我从一本书上得到这个，但每次我使用它，我都会出错。 语法错误：语法无效

path = '/home/foad/PythonBoken/flash/'

import numpy as np
from random import gauss

a = [gauss(1.5, 2) for i in range(100000)] #generation of normally distributed randoms

#Write this list above to disk for later retrieval
import pickle 

pkl_file=open(path + 'data.pkl', 'w') #open file for writing. Existing file may be overwritten

%time pickle.dump(a, pkl_file)