import re
str_ = "8983605653Sudanshu452365423256Shinde"
m = re.match(r"(\d{10})([A-Za-z]{8})(\d{12})([A-Za-z]{6})",str_)
if m:
print(list(m.groups()))
aW1wb3J0IHJlCgpzdHJfID0gIjg5ODM2MDU2NTNTdWRhbnNodTQ1MjM2NTQyMzI1NlNoaW5kZSIKbSA9IHJlLm1hdGNoKHIiKFxkezEwfSkoW0EtWmEtel17OH0pKFxkezEyfSkoW0EtWmEtel17Nn0pIixzdHJfKQppZiBtOgogICAgcHJpbnQobGlzdChtLmdyb3VwcygpKSk=