Python的难度

Question

def myfunc(x):
 y = x
 y.append('How do I stop Python from modifying x here?')
 return y

x = []
z = myfunc(x)
print(x)

Answer 1

你做：

y = x[:]

制作清单x的副本。

Answer 2

在修改X之前需要复制X，

def myfunc(x):
 y = list(x)
 y.append('How do I stop Python from modifying x here?')
 return y

x = []
z = myfunc(x)
print(x)