import re

ip = "{kevin.knerr, sam.mcgettrick, mike.grahs}@google.com.au"	
arr = re.match(r"\{([^\}]+)\}(\@\S+$)", ip)

#Using split for solution

for x in arr.group(1).split(","):
	print (x.strip() + arr.group(2))

#Regex Based solution

arr1 = re.findall(r"([^, ]+)", arr.group(1))
for x in arr1:
	print (x + arr.group(2))