Installing pythonstartup file

Question

How do I install the pythonstartup file so that it runs on command like python myfile.py?

I tried to install it into my /home/myuser<

Answer 1

How to execute the python file defined in $PYTHONSTARTUP when you execute a file like python foobar.py

Run this command to find out where your OS has defined USER_SITE:

$ python -c "import site; site._script()" 

Mine says:

USER_SITE: '/home/el/.local/lib64/python2.7/site-packages'

Create a new file there called /home/el/.local/lib64/python2.7/site-packages/usercustomize.py, put this code in there:

try:
    import your_things
    import readline
    print("ROCKETMAN!")

except ImportError:
    print("Can't load your things")
    print("Either exit here, or perform remedial actions")
    exit()

Close the terminal and reopen it to clear out any shenanigans.

Make a new file python foobar.py anywhere on the filesystem, put this code in there:

#Note there is no your_things module imported here.
#Print your_things version:
print(your_things.__version__)

Run it:

python foobar.py 
ROCKETMAN!
'1.12.0'

What just happened.

You used the python sitewide specific python configuration hook and imported libraries in the usercustomize.py file which ran before foobar.py.

Documentation: https://docs.python.org/2/library/site.html

Where I found this trick: https://nedbatchelder.com/blog/201001/running_code_at_python_startup.html