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You will find on this page some useful, but unsorted, python tips and tricks that can't fit in a section of the main JYP's recommended steps for learning python page
* Reading/setting environments variables
>>> os.environ['TMPDIR'] '/data/jypmce/climafcache' >>> os.environ.get('SCRATCHDIR', '/data/jypmce/some_scratch_stuff') '/data/jypmce/some_scratch_stuff' >>> os.environ['temporary_env_var_for_THIS_script'] = 'some value' >>> os.environ['temporary_env_var_for_THIS_script'] 'some value'
* Generating (aka raising) an error. This will stop the script, unless it is called in a function, and the code calling the function explicitely catches and deals with errors
raise RuntimeError('\n\nOMG! An error! :-(\nAborting script...')
* Stopping a script
sys.exit('Some optional message about why we are stopping')
* Checking if a file/directory is writable by the current user
>>> os.access('/', os.W_OK) False >>> os.access('/home/jypmce/.bashrc', os.W_OK) True