Can't use '\1' backreference to capture-group in a function call in re.sub() repr expression

Question

I have a string S = '02143' and a list A = ['a','b','c','d','e']. I want to replace all those digits in 'S' with their corresponding element in list A.

For example, replace 0 with A[0], 2 with A[2] and so on. Final output should be S = 'acbed'.

I tried:

S = re.sub(r'([0-9])', A[int(r'\g<1>')], S)

However this gives an error ValueError: invalid literal for int() with base 10: '\\g<1>'. I guess it is considering backreference '\g<1>' as a string. How can I solve this especially using re.sub and capture-groups, else alternatively?