No.
Let me clarify. Mel and python live in a dynamic environment. So there is no way you can prevent a user from dumping the code out. Mel protector has a slightly nifty trick up its sleeve. But alas no help i can still just trick melprotector to thinking i am maya. Besides even if i couldnt i can just read the code from a debugger.
So now defining protected as protected from whom? Casual users sure no problem, just port to python and send the pyc file. Protected from a attacker that wants your code, no way.
Problem one is that mac can be easily faked. Hell i can copy the computer with wmvare and youll newer know. Second web trafic is easy to kill.
Anyway dont use python if you dont want to make it easy. C is the way to go. Th resond for this is that operating systems provide pretty good defences for this. And if ist c its harder to strat bugging out. For example windows has this piece of api that gives you hash for the computer and cumulative date. This code can ensure that the time limit can not be circumvented easily. Tough again impossible to use against persitent attacker.
Now since your code can not be protected from people you dont trust. then the easy answer is dont send it to people you dont trust. Make a contract, called a license. Give peopel value for your money and they wont bother to even attack/misuse a plain text file.