python 3 : Change one character of item in list

我有一个这样的列表:

['ID|number1|number2|+|name|location','ID2|number3|number4|-|name2|location2'] 

该列表是从字典生成的，并包含字典的键。我 想改变第一个'|'变成一个“=”。

我试过这个:

keyList=[] 
for item in finalDict.keys(): 
    keyList.append(item) 
 
z=0 
for item in keyList: 
    for letter in item: 
        if letter=='|': 
            z+=1 
            if z==1: 
                letter.replace('|', '=') 

但我没有得到错误或我想要的输出

Actual output: 
    ['ID|number1|number2|+|name|location','ID2|number3|number4|-|name2|location2'] 
 
 
Desired output: 
    ['ID=number1|number2|+|name|location','ID2=number3|number4|-|name2|location2'] 

请您参考如下方法:

to change the first '|' into a '='

简单来说:

keyList = ['ID|number1|number2|+|name|location','ID2|number3|number4|-|name2|location2'] 
result = [k.replace('|', '=', 1) for k in keyList] 
 
print(result) 

输出:

['ID=number1|number2|+|name|location', 'ID2=number3|number4|-|name2|location2'] 

• str.replace(old, new[, count]) - 如果可选参数 count 是 给定，只有第一个出现的次数被替换。