when you start python from system command line ( shell promptor command prompt window)you can pass in variety of option flags to control how python runs your code unlike the system-wide environment variables of the prior sectioncommand-line arguments can be different each time you run script the complete form of python command-line invocation in looks like this ( is roughly the samewith few differences described ahead)python [-bbdehioqssuvvwxx[- command - module-name script [argsthe rest of this section briefly demonstrates some of python' most commonly used arguments for more details on available command-line options not covered heresee the python manuals or reference texts or better yetask python itself--run command line form like thisc:\codepython - to request python' help displaywhich documents all available command-line options if you deal with complex command linesbe sure to also check out the standard library modules in this domainthe original getopthe newer argparseand the now-deprecated (since optparsewhich support more sophisticated command-line processing also see python' library manuals and other references for more on the pdb and profile modules the following tour deploys running script files with arguments most command lines make use of only the script and args parts of the last section' python command-line formatto run program' source file with arguments to be used by the program itself to illustrateconsider the following script-- text file named showargs pycreated in directory :\code or another of your choosing--which prints the command-line arguments made available to the script as sys argva python list of python strings (if you don' yet know how to create or run python script filessee the full coverage in and we're interested only in command-line arguments here)file showargs py import sys print(sys argvin the following command lineboth python and showargs py can also be complete directory paths--the former is assumed to be on your path hereand the latter is assumed to be in the current directory the three arguments ( -cmeant for the script show up in the sys argv list and can be inspected by your script' code therethe first item in sys argv is always the script file' namewhen it is knownc:\codepython showargs py - ['showargs py'' '' ''- ' appendix ainstallation and configuration most commonrun script file