import re

st3 = ("Operational.1252.Devi\n"
            "Staff.1875.Erin\n"
            "Operational.1552.Dave\n"
            "Staff.1875.Hutri\n"
            "Operational.1952.Liana\n"
            "Management.1292.Ricky\n"
            "Staff.1875.Udin\n"
            "Management.1852.Oswyne\n"
            "Staff.1875.Udin\n"
            "Operational.1052.Devi\n"
            "Management.1282.Putra\n"
            "Operational.1262.Kelvin\n"
            "Admin.9823.Gilang\n"
            "Staff.1275.Siska\n"
            "Staff.1835.Udin\n"
            "Admin.9823.Gilang\n"
            "Staff.1875.Silalahi\n"
            "Management.1282.Delvin\n"
            "and more List....")
pattern = r"^(?:Operational|Management|Admin|Staff)\.[0-9]{1,4}(\..+)"

result = sorted(set(re.findall(pattern, st3, re.M)))
print(result)