This question already has answers here:
How to get environment from a subprocess?
(7 answers)
Closed 4 years ago.
I try execute csh script(which creates or updates environment variables) from python but environment variables don't update after return to shell.
Why ? How can I solve it ?
subprocess.call('script.csh',shell=True,executable="/bin/csh")
To set an environment variable in python, use
os.environ['YOUR_VARIABLE'] = "your_value"
Note that environment variables must be strings.
Explanation for why you cannot do what you want to do:
Environment variables are set in a per process memory space. When bash (or whatever shell have you) runs a program, it uses fork(), which inherits bash’s variables because it is a child process. What your trying to do is create a child process and have he parent inherit from the child, like #PM 2Ring said.
Related
This question already has answers here:
Passing IPython variables as arguments to bash commands
(4 answers)
Running Bash commands in Python
(11 answers)
Closed 2 years ago.
So I found this tool: https://github.com/elceef/dnstwist and I want to pass a list of domains into that tool then take the output and visualize it.
It operates through the command line, but how do I automate entering each domain and process the output automatically as well?
By the way I am using colab, so I would need a solution using jupyter notebooks!
Thanks!
If you want to do this programmatically I would not use the provided cli – although this would also be possible.
Instead you can create a small python script to do this.
Import dwintwist in your script and have a look at the main function in dwintwist.py to see how you call this.
Doesn't look to hard, but I don't know your programming skill level of course.
This question already has answers here:
Test if code is executed from within a py.test session
(6 answers)
Closed 3 years ago.
I want to set a variable in my Python code to different values, according to whether it is running in unit tests or in production.
Assuming we can't pass additional parameters to the test runners, or we don't have any environment variables set in production environment.
A_LOCAL_VARIABLE = 1 if is_running_by_pytest() else 0
My expectation is that by checking whether the code is running under the pytest runner, I can change the value of the variable.
Ideally, if the code is ran by the pytest runner, there're some pre-defined environment variables that we can use to identify it. But I cannot find documentations, or I was using the wrong keywords.
You can use a configuration variable. Each of our executable environments have its own configuration file. Some of our tests use different values for different environments like Single Sign On tests.
This question already has answers here:
How to get local variables updated, when using the `exec` call?
(3 answers)
Closed 4 years ago.
In my main script, I import one of my own module which contains global variables. This main script execute another script with the function exec (exec(compile(open(Seq_1, "rb").read(), Seq_1, 'exec')) and this other script import the same module.
So my question is: does these scripts have access to the same global variables (that means if I modify one global variable, the other script will be impacted) or not?
Python will run your file when you first import it. On the second import python won't re-run the file.
In practice, python functions and variables directly on modules (not wrapped in classes) works like singletons.
This answer explains more about it. You can directly refer to the docs, also suggested on linked answer.
I used to code in Matlab in which it's easy to see the saved variables in the workspace window. So for example a = [1,2,3] can be easily found in the workspace window.
Now I started to use python in Pycharm. In Python I can create the same variable, a = [1,2,3] but there isn't a window which shows me all the variables already created in the script. Having only 1 variable isn't a problem but when defining a lot of variables it can be difficult to know which variables are already defined ant what these variables contain.
My Question:
How does one have a good overview of all variables in Python (Pycharm)? Is there a similar window like the Workspace window of Matlab in Pycharm?
You can use the Debug Tool Window to examine the variables stored in your application.
More information can be found here: (PyCharm 2016.3)
https://www.jetbrains.com/help/pycharm/2016.3/debug-tool-window-variables.html
This question already has answers here:
How can I access environment variables in Python?
(16 answers)
Closed 9 years ago.
I'm new to Python and would like reproduce a convenience I used when working in Perl.
When calling a Perl script I usually set some $ENV variables (like VERBOSE, DEVELOP and DEBUG). Inside the called script I recover their values using
my $verbose=$ENV{VERBOSE};
my $develop=$ENV{DEVELOP};
my $debug=$ENV{DEBUG};
This allow print stmts conditional on these variables.
Can I do the same thing in Python? I know thanks to previous responses (Thank you!) to use os.environ[var] within the script to access the values. But I have not been able to figure out how to assign a value to a variable when I call the script from the command line as I could when callinbg a Perl script
Can values be set for such variables on the commandline invoking a python script?
TIA
They are accessible via the os.environ dictionary.
os.environ['VERBOSE']