how can merged byte string split to normal string

Question

There is some data which stored improperly in the program, the original process will be like

a=b'abcd'
b=b'cded'
with open('text.txt','w') as wfp:
    wfp.write(str(a))
    wfp.write(str(b))

and sure the output string in text.txt becomes b'abcd'b'cded' how can this perform a reverse operation that split and assign as two variables, I tried to like this but not working, only return ['','','']

import re
with open('text.txt','r') as fp:
    content = fp.read()
    re.split("""b'\w+'""",content)