Python3: equivalent of "export VARNAME" in terminal [duplicate] - bash

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In terminal (bash) on OSX I can set an environment variable, using the syntax export VARNAME=1 or export VARNAME="hello"; and that persist as long as the session is running, or until the terminal window is closed.
What would be the equivalent form, to do the same via Python3? I would like to avoid to call Popen just to set a global variable.
Also I need this variable only for the purpose to run my python code; once the script is done, I do not need it anymore; so even if it last only for the lifespan of my script running, it is acceptable.

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I have some code that looks like this:
export AWS_REGION='us-east-1'
export CLUSTER_NAME='my_cluster'
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Thanks
declare, as any other statement that modifies a variable within a shell, only does so within the current environment. As the shell does not somehow save its environment on eixst and load it again when restarted, you can just close your shell and open a new one and you'lll have your initial environment back.
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How can I access an environment variable from another? I have the following in my shell
#!/usr/bin/env bash
set -x
export A_version=1.0.0
component=A
echo ${${component}_version}}
the bash script after the run gives me
temp.sh: line 9: ${${component}_version}}: bad substitution
You can use eval to do this. Here is a working version of your script that prints 1.0.0:
export A_version=1.0.0
component=A
eval "echo \$${component}_version"
For more information, see this page:
http://tldp.org/LDP/abs/html/ivr.html
Update: A safer way to do the same thing in Bash would be:
export A_version=1.0.0
component=A
var=${component}_version; echo "${!var}"
Note that you have to run this script with bash, not sh.

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