The ONLY way to know what you got is to buy from a reputable breeder that owns the parents and provides a guarantee for their hets. Not all markers mean its definitely a het. I have a 100% het pied male with markers, but there is always the chance the man lied (first ball python, didn't think to buy from a well known breeder) and I just have a normal.
Yeah only buy a het if it is from a reputable breeder and you have seen the parents personally and there is proof that these are the offspring. Don't trust someones word of even if they type it up, written word isn't good enough.
6.5.15 Animals
1.2 Pomeranian's
0.1.15 Tropical Fish 2.2 Snakes:
0.1 2009 100% Het Piebald
0.1 Normal
1.0 Green Tree Python
1.0 Brazilian Rainbow Boa