剛才自己寫的
def TimeFormat(str):

pdb.set_trace()
#20180402:154101 -> 2018-04-02 15:41:01
time_stamp = ""
index = 0 
for c in str:
    if index == 4 or index == 6:
        time_stamp += '-' 
    if index == 8:
        time_stamp += ' ' 
        index = index + 1 
        continue
    if index == 11 or index == 13: 
        time_stamp += ':' 

    index = index + 1 
    time_stamp += c
    
return time_stamp

用datetime庫就好了

>>> from datetime import datetime
>>> old = '20180402:154101'
>>> dt = datetime.strptime(old, '%Y%m%d:%H%M%S')
>>> new = dt.strftime('%Y-%m-%d %X')
>>> print(new)
2018-04-02 15:41:01

當然你也可以純用字符串處理達到相同的效果

這樣？datetime.datetime.strptime('20180402:154101', '%Y%m%d:%H%M%S')