Can't mutate dictionaries from python

I am trying to modify `ENV` or other vars from python, but it's not working.
I'm using Python 3.9.12 and Julia 1.7.3, PyCall v1.93.1, pyjulia 0.5.7.
```
>>> import julia
>>> julia.install('C:\\Users\\Azathoth\\AppData\\Local\\Programs\\Julia-1.7.3\\bin\\julia.exe')
>>> Julia(runtime='C:\\Users\\Azathoth\\AppData\\Local\\Programs\\Julia-1.7.3\\bin\\julia.exe')
>>> from julia import Base, Main
>>> Main.a_dict = Base.Dict()
>>> Main.a_dict
{}
>>> Main.a_dict["a"] = True
>>> Main.a_dict
{}
```