Make vm.import_from_str() so we can import string python programs as modules

[lattice0]

Summary

Make an option to vm.import_from_str(). Currently, vm.import expects us to have a file path, and thus the python file needs to be somewhere in the system or maybe in a virtual file system. For some cases the python file could come as a string. I know that the mini repl allows us to run runtime generated python code, but there's no way to turn a string python program into a module inside the VM so I can then get the function attribute and call it with arguments.

#5173 is what I tried to do

Expected use case

Run python programs generated at runtime, but also be able to get its attributes like functions and call them with arguments. Currently we can only compile a string and run it, no way to turn it into a module on the VM

[youknowone]

Related to #5041
I think having this one is convenient for embedded interpreters

[youknowone]

#5214 added a similar feature. Thank you for suggestion!