d = {
"age": "76",
"Bank": "98310",
"Stage": "final",
"idnr": "4578",
"last number + Value": "[345:K]"
}
last = list(d.keys())[-1]
d["Total data"] = dict(
zip(
last.strip().split('+'),
d[last].strip("[]").split(':')
)
)
print(d)
ZCA9IHsKICAgICJhZ2UiOiAiNzYiLAogICAgIkJhbmsiOiAiOTgzMTAiLAogICAgIlN0YWdlIjogImZpbmFsIiwKICAgICJpZG5yIjogIjQ1NzgiLAogICAgImxhc3QgbnVtYmVyICsgVmFsdWUiOiAiWzM0NTpLXSIKfQoKbGFzdCA9IGxpc3QoZC5rZXlzKCkpWy0xXQpkWyJUb3RhbCBkYXRhIl0gPSBkaWN0KAogICAgemlwKAogICAgICAgIGxhc3Quc3RyaXAoKS5zcGxpdCgnKycpLAogICAgICAgIGRbbGFzdF0uc3RyaXAoIltdIikuc3BsaXQoJzonKQogICAgKQopCnByaW50KGQp