import re
array = ['GW-date45:ger-date45:mySAPgives','DC-date48ccc:date48:mySAP']
hostname = []
for node in array:
	m = re.search(r'^[^-]*-([^:]+)', node)
	if m:
		hostname.append(m.group(1))

for line in hostname:
    print(line)