Python不识别函数中的局部变量

我声明了一个变量x，它是函数output = model(x)的输入。调用后x获得与output变量相同的值。我原以为呼叫前后x应该相同，但事实并非如此。代码的行为就像函数model中的output变量和局部变量是指向x的指针一样。你能解释一下这种行为吗？我从未在Fortran、C/C++和Matlab中遇到过类似的东西。下面是我的python代码示例

import numpy as np

def model(aux):    
    for i in range(0,len(aux)):       
        aux[i] = np.sin( aux[i] ) + 1      
    return aux

length = 5

x =  np.linspace(0,1,length)  

print('\n X variable  BEFORE the function call \n')
for i in range(0,length):
    print('x [',i,'] =',  x[i])

output = model(x)

print('\n X variable  AFTER the function call \n')
for i in range(0,length):
    print('x [',i,'] =',  x[i])       

print('\n Output variable  AFTER the function call \n')    
for i in range(0,length):
    print('output [',i,'] =',  output[i])  

这里的广告是我得到的：

 X variable  BEFORE the function call 

x [ 0 ] = 0.0
x [ 1 ] = 0.25
x [ 2 ] = 0.5
x [ 3 ] = 0.75
x [ 4 ] = 1.0

 X variable  AFTER the function call 

x [ 0 ] = 1.0
x [ 1 ] = 1.247403959254523
x [ 2 ] = 1.479425538604203
x [ 3 ] = 1.6816387600233342
x [ 4 ] = 1.8414709848078965

 Output variable  AFTER the function call 

output [ 0 ] = 1.0
output [ 1 ] = 1.247403959254523
output [ 2 ] = 1.479425538604203
output [ 3 ] = 1.6816387600233342

X变量BEFORE和AFTER不应该相同吗？