Finding average of the numbers in each line Python

I have a program which grabs the drivers laptimes and writes them to a txt file.
output.txt looks like this:

 00:01:26.102
 00:01:15.618
 00:01:15.096
 00:01:14.792
 00:01:14.532
 00:01:25.083
 00:01:25.497
 00:01:17.809
 00:01:19.364
 00:01:18.935
 00:01:18.076
 00:01:18.111
 00:01:22.086
 00:01:20.500
 00:01:18.167
 00:01:18.268
 00:01:18.373
 00:01:17.950
 00:01:17.944

I want to sum all the lap times and divide it by lap count(basically find the average of them). But i cant manage to sum them correctly. How can i do it?

>Solution :

You can use timedelta

import datetime as dt

def avg_time(lst:list):
    n=len(lst)
    print(n)
    res=[]
    for i in lst:
        hour,minute,second =i.split(":")
        second,milli=second.split(".")
        res.append(dt.timedelta(hours=int(hour),minutes=int(minute),seconds=int(second),milliseconds=int(milli)))
    return sum(res,res[0])/n


t = ["00:01:26.102","00:01:15.618","00:01:15.096","00:01:14.792","00:01:14.532","00:01:25.083","00:01:25.497","00:01:17.809","00:01:19.364",
"00:01:18.935","00:01:18.076","00:01:18.111","00:01:22.086","00:01:20.500","00:01:18.167","00:01:18.268","00:01:18.373","00:01:17.950","00:01:17.944",]

a = avg_time(t)
print(a)

Output:

0:01:23.600263

PS. you can not format timedelta like other datetime object. So you can use some normal Maths to get it as follows:

total_second=a.total_seconds()
hour_s,second_s=divmod(total_second,3600)
minute_s,second_s=divmod(second_s,60)