'''Для обработки MAC-ов LAN
   Приводит маки к виду xxxx.xxxx.xxxx
'''

file_write = open("output.txt", 'w', encoding='utf-8')
with open("1.txt", 'r', encoding="utf-8") as r_file:
    while True:
        line = r_file.readline()
        if not line:
            break
        # Удаление лишних символов
        if '-' in line or ':' in line:
            line = line.replace("-", ".").replace(":", ".").replace("\n", "").lower() 
            line = line[0:2]+''+line[3:5]+''+line[5:8]+''+line[9:12]+line[12:14]+''+line[15:] 
            file_write.write(line+'\n')
            continue
        else:
            file_write.write(line)