import re
s='address:\n 123 beautiful house \n ---blabla--- \n another street \n ---more blabla--- \n ---extra bla--- \n one country\n---a lot blabla'
value = re.search('address:\n((?:.*\n){1,6})',s)
if value:
	lines = value.group(1).splitlines()
	print(lines[0].strip())
	if len(lines) > 2:
		print(lines[2].strip())
	if len(lines) > 5:
		print(lines[5].strip())