You’re trying to open each file twice! First you do:
infile=open('110331_HS1A_1_rtTA.result','r')
and then you pass infile (which is a file object) to the open function again:
with open (infile, mode="r", buffering=-1)
open is of course expecting its first argument to be a file name, not an opened file!
Open the file once only and you should be fine.