import re
myText = 'sgasgAAAaoasgosaegnsBBBausgisego'
myRegex = re.compile('(?P<long>(?P<short>AAA)(?:.*BBB)?)')
x = myRegex.search(myText).groupdict()
print(x)
aW1wb3J0IHJlCm15VGV4dCA9ICdzZ2FzZ0FBQWFvYXNnb3NhZWduc0JCQmF1c2dpc2VnbycKbXlSZWdleCA9IHJlLmNvbXBpbGUoJyg/UDxsb25nPig/UDxzaG9ydD5BQUEpKD86LipCQkIpPyknKQp4ID0gbXlSZWdleC5zZWFyY2gobXlUZXh0KS5ncm91cGRpY3QoKQpwcmludCh4KQ==