import re
rx = r"^[^:-][^:]*"
text = "enx002: connected to Wired connection 2\ndocker0: connected to docker0\nvirbr0: connected to virbr0\ntun0: connected to tun0"
print( re.findall(rx, text, re.M) )
print( re.findall(r'^([^:\n-][^:\n]*):', text, re.M) )
aW1wb3J0IHJlCnJ4ID0gciJeW146LV1bXjpdKiIKdGV4dCA9ICJlbngwMDI6IGNvbm5lY3RlZCB0byBXaXJlZCBjb25uZWN0aW9uIDJcbmRvY2tlcjA6IGNvbm5lY3RlZCB0byBkb2NrZXIwXG52aXJicjA6IGNvbm5lY3RlZCB0byB2aXJicjBcbnR1bjA6IGNvbm5lY3RlZCB0byB0dW4wIgpwcmludCggcmUuZmluZGFsbChyeCwgdGV4dCwgcmUuTSkgKQpwcmludCggcmUuZmluZGFsbChyJ14oW146XG4tXVteOlxuXSopOicsIHRleHQsIHJlLk0pICkK