如何在 Python 函数中通过引用传递参数？
在Python中，函数参数总是通过引用传递。这可以通过检查id()事实、形式参数和返回的对象来验证
def foo(x):
print ("id of received argument",id(x))
x.append("20")
return x
a = ["10"]
print ("id of argument before calling function",id(a))
b = foo(a)
print ("id of returned object",id(b))
print (b)
print (a)在id()A，X内部的foo()和b被发现是相同的。
id of argument before calling function 1475589299912 id of received argument 1475589299912 id of returned object 1475589299912