import re
s = """Model Number : 123
Serial Number : 456"""
model_number = re.findall(r'Model Number\s*:.*',s)
print(model_number)
aW1wb3J0IHJlCnMgPSAiIiJNb2RlbCBOdW1iZXIgOiAxMjMgCiAgICAgICAgICAgIFNlcmlhbCBOdW1iZXIgOiA0NTYiIiIKbW9kZWxfbnVtYmVyID0gcmUuZmluZGFsbChyJ01vZGVsIE51bWJlclxzKjouKicscykKcHJpbnQobW9kZWxfbnVtYmVyKQ==