Python: Replace values while reading CSV file with pandas

i've a txt file that contains something like this:

Struct{a,b,c}
Struct {d,f,z}

I'd like to read this file and have this output:

  0   1   2
0 a   b   c
1 d   f   z

I tried to run this code

import numpy as np
import pandas as pd
def conv(val, default_val=''):
    try:
         return (val)
    except ValueError:
         return default_val
x = pd.read_csv('/Users/me/Desktop/connector/connector.txt', sep=",", header=None, converters={'Struct': conv, '{': conv, '}': conv })
print(x)

but this is the output:

          0  1   2
0  Struct{x  y  z}
1  Struct{a  b  c}

can somebody tell me why it doesn't work?