Does the lack of actual hiding essentially make all of Python open source?
you can ship files with python byte code (pyc files) which are not readable directly but can be decompiled and read. you can use obfucators to mess with the code to make it less readable. this will change names of functions and variables to some nonsense (and some other stuff), so it will be harder to continue to develop on top of that code. apart from that i don't think there is a real way to protect python code. keep in mind that java also suffers from this problem and i would say probably all other languages which use some kind of virtual machine to execute the code.