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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 check_command(args):
 """Checks that all dependencies in the specified requirements file are up to date."""

    outdated = check_requirements_file(args.requirements_file,
                                       args.skip_packages)

    if outdated:
        print('Requirements in {} are out of date:'.format(
            args.requirements_file))

        for item in outdated:
            print(' * {} is {} latest is {}.'.format(*item))

        sys.exit(1)
    else:
        print('Requirements in {} are up to date.'.format(
            args.requirements_file))