import re
a = [' /abc/def/zx -a 12 -b 12 -c 14 -d 15 --pqr -A $done1 ', 'abc','def']
for index, x in enumerate(a):
a[index] = re.sub('(.*zx )(.*)( -A \$done1)', r'\g<1>time\g<3>', x)
print(a)
aW1wb3J0IHJlCgphID0gWycgIC9hYmMvZGVmL3p4IC1hIDEyIC1iIDEyIC1jIDE0IC1kIDE1IC0tcHFyIC1BICRkb25lMSAgJywgJ2FiYycsJ2RlZiddCmZvciBpbmRleCwgeCBpbiBlbnVtZXJhdGUoYSk6CiAgICBhW2luZGV4XSA9IHJlLnN1YignKC4qenggKSguKikoIC1BIFwkZG9uZTEpJywgcidcZzwxPnRpbWVcZzwzPicsIHgpCiAgICAKcHJpbnQoYSk=