RUSTPYTHONPATH is not set when using `Settings::default()` without clap

Summary

I've manually set the RUSTPYTHONPATH in the system environment variable, Rust sees the correct folder location prior to calling the vm::Interpreter::without_stdlib(Default::default()).enter(|vm| { ..

and yet, the following error appears:

encodings initialization failed. Only utf-8 encoding will be supported. ModuleNotFoundError: No module named 'encodings'

The above exception was the direct cause of the following exception:

RuntimeError: Could not import encodings. Is your RUSTPYTHONPATH set? If you don't have access to a consistent external environment (e.g. if you're embedding rustpython in another application), try enabling the freeze-stdlib feature

Expected

No message

Actual

encodings initialization failed. Only utf-8 encoding will be supported. ModuleNotFoundError: No module named 'encodings'

The above exception was the direct cause of the following exception:

RuntimeError: Could not import encodings. Is your RUSTPYTHONPATH set? If you don't have access to a consistent external environment (e.g. if you're embedding rustpython in another application), try enabling the freeze-stdlib feature

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