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Cannot read environment variable set with PowerShell with os.environ.get

A bit of a random problem here. I set an environment variable using PowerShell like this:
$env:GOOGLE_ELEVATION_API="the_api-key"
Then in python I attempt to read it with this simple script:
from os import environ
key = environ.get("GOOGLE_ELEVATION_API")
This returns None. If I query my environment variables in PowerShell it is there. If I query it through python with os.environ it is not.
None of the results I found make reference that this should be an issue, neither on the PowerShell side nor on python's side. I have not restarted my machine since I honestly do not believe this is what should be done. I did restart my IDE in the hope that it is somehow caching the environment but thankfully it does not.
Any pointers would be great!

Setting an environment variable via PowerShell's $env: namespace defines it for the current process only.
Any Python scripts invoked directly from a PowerShell session would see such variables, however, because child processes inherit the caller's environment variables.
To persistently define a Windows environment variable at the machine level that all processes see, you must use .NET APIs directly (as of PowerShell 7.1):
# Note: Requires ELEVATION, due to setting at the *machine* level.
[Environment]::SetEnvironmentVariable('GOOGLE_ELEVATION_API', 'the_api-key', 'Machine')
Note that only future PowerShell sessions will see this variable, and the need to restart an application in order for it to see the new variable typically also applies to other running applications.
(The exception are those applications that actively listen for the WM_SETTINGCHANGE message and refresh their environment in response, which is what the Windows GUI shell (explorer.exe) does.)
For more information about persistently setting environment variables on Windows, see this answer.

os.getenv('CORENLP_HOME') returning None and os.environ['CORENLP_HOME'] returning KeyError but echo $CORENLP_HOME returns a path in terminal

I am aware a lot of similar questions exist but I am unable to understand what is happening here. I am trying to follow instructions for this Stanford CoreNLP python wrapper here, one of the steps is to set theCORENLP_HOME environment variable.
I ran the command:
export CORENLP_HOME=/path/to/stanford-corenlp-full-2018-10-05
Restarted the terminal, or actually added to my ~/.bash_profile. Now when I do a echo $CORENLP_HOME in the terminal I am able to see the path correctly. But on the other hand, if the corenlp wrapper code tries to find the same path through python code it returns None.
So I separately checked two python commands, the wrapper code uses os.getenv():
import os
print(os.getenv('CORENLP_HOME')) #prints None
print(os.environ['CORENLP_HOME']) #Throws a KeyError exception
MacOS version: 10.15.4;Python: 3.7.6
I don't have a very deep understanding of environment variables in general, I want to understand what is happening here, or if I am missing something simple. Happy to provide more information!

Environment variables are not global in the UNIX process model. Each process is provided a set of environment variables by the parent process that starts it. That is typically a copy of the parent's environment variables. If you are not starting pycharm from the shell that ran the export command pycharm won't see that shell's environment variables.
The behavior you describe means you are not starting pycharm from the shell that did the export CORENLP_HOME=/path/to/stanford-corenlp-full-2018-10-05.
P.S., The UNIX process model also means that a process cannot modify the environment variables of a different process.

Python : How to set environment variables on VM windows

I want to write a python script that adds env variables to PATH. This script will be executed from ssh to windows virtual machine. I tried 2 methods and no one works.
Method 1 :
os.system("setx /M PATH "'"%PATH%;path1;path2"'"")
Method 2 :
os.environ["PATH"] += os.pathsep + os.pathsep.join(["path1"])
Could you help me please ?
Thanks in advance.

You’ll need an administrative command prompt.
Try:
setx EC2_HOME "" /M

Perhaps try this as a variation to your second method
os.environ["PATH"] = os.pathsep.join([os.environ["PATH"], "path1"])
Also check out some of the documentation here related to running python on Windows machines https://docs.python.org/3.4/using/windows.html
Specifically it is mentioned that you can set environment variables outside of your python environment by using the following syntax
set PYTHONPATH=%PYTHONPATH%;C:\My_python_lib

Thanks for your answers.
Finally, I found the problem, I was setting this env variables with running a subprocess that execute another script, when I set this env vars from the script without a subprocess, it works and the two methods works :)

os.environ doesn't see some variables

I have one problem with os.environ. I set some variables in my bat file (for example):
set MYDIR=%CURDIR%
Then I use set command in command line of Windows to check it. Everything is fine, my variable was added. But!
Then I run my Python script and use os.environ['MYDIR'] or os.getenv('MYDIR') but my envorinment variable doesn't show up!
Why does it happen?
My OS - Windows 7 x64, Python 2.5.4
Thanks.

Set works on session level. WinXP, use SETX from support tools http://www.microsoft.com/en-us/download/details.aspx?id=18546 to permanently set env variable.
Or use MyComputer>Properties>Advanced>Environment Variables to set user- and system- level variables.
Never used PyCharm, but breef scan through docs shows that you might be able to set script-level environment variables within PyCharm, look here http://www.jetbrains.com/pycharm/webhelp/run-debug-configuration-python.html

Setting environment variables in the current environment with python (win32com)

I'm trying to use python to set environment variables that will persist in Pythons parent environment, even after python exits back to the shell, but will not persist once the parent shell is closed. Opening a new shell should require that the python script be run again in order to set the environment correctly.
Based off the recommendations from this post, I'm trying to do this using the win32com python library. Unfortunately, I have very little experience with the win32 api.
Basically, I need a way to get a handle to the current environment, and set environment variables in such a way that they will persist in python's parent environment, but will not persist after the parent environment exits.

The linked post tells how to change the default environment which will affect new processes. It manipulates registry values.
"A process can never directly change the environment variables of another process that is not a child of that process", says MS documentation. So you'll never reach your stated goal from within a child process, Python or not.

It is impossible to change the environment of the parent, by design. The best you can do is have your program emit commands that alter the environment, and then the caller of your program needs to eval the output of your command.