How to open an unicode text file inside a zip?

I tried

with zipfile.ZipFile("5.csv.zip", "r") as zfile:
    for name in zfile.namelist():
        with zfile.open(name, 'rU') as readFile:
                line = readFile.readline()
                print(line)
                split = line.split('\t')

it answers:

b'$0.0\t1822\t1\t1\t1\n'
Traceback (most recent call last)
File "zip.py", line 6
    split = line.split('\t')
TypeError: Type str doesn't support the buffer API

How to open the text file as unicode instead of as b?