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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def run(app, argv=sys.argv, extra_args=None):
 """ Run commands in a plain django environment :param app: application :param argv: arguments (default to sys.argv) :param extra_args: list of extra arguments """

    if app not in argv[:2]:
        # app is automatically added if not present
        argv.insert(1, app)
    if len(argv) < 3 and 'test' not in argv[:2]:
        # test argument is given if not argument is passed
        argv.insert(2, 'test')
    if extra_args:
        argv.extend(extra_args)
    return runner(argv)