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Please check out the full documentation of configparse in the official Python documentation: https://docs.python.org/3/library/configparser.html.

In most cases, this configuration parser should be good enough, but if more power is needed, you can use YAML files as configuration files. YAML files (https://learn.getgrav.org/advanced/yaml) are very common as configuration files, and are better structured and can be parsed directly, taking into account data types.

1. Add PyYAML to the requirements.txt file and install it: 

PyYAML==3.12

2. Create the prepare_task_yaml.py file:

import yaml
import argparse
import sys


def main(number, other_number, output):
    result = number * other_number
    print(f'The result is {result}', file=output)


if __name__ == '__main__':
    parser = argparse.ArgumentParser()
    parser.add_argument('-n1', type=int, help='A number', default=1)
    parser.add_argument('-n2', type=int, help='Another number', default=1)

    parser.add_argument('-c', dest='config', type=argparse.FileType('r'),
 help='config file in YAML format',
 default=None)
    parser.add_argument('-o', dest='output', type=argparse.FileType('w'),
                        help='output file',
                        default=sys.stdout)

    args = parser.parse_args()
    if args.config:
        config = yaml.load(args.config)
        # No need to transform values
        args.n1 = config['ARGUMENTS']['n1']
        args.n2 = config['ARGUMENTS']['n2']

    main(args.n1, args.n2, args.output)

3. Define the config file config.yaml, available in GitHub https://github.com/PacktPublishing/Python-Automation-Cookbook/blob/master/Chapter02/config.yaml :

ARGUMENTS:
    n1: 7
    n2: 4

4. Then, run the following:

$ python3 prepare_task_yaml.py -c config.yaml
The result is 28

There's also the possibility of setting a default config file, as well as a default output file. This can be handy to create a pure task that requires no input parameters.