Command Line Argument | Python
import argparse
parser = argparse.ArgumentParser(description='Parse command line options.')
parser.add_argument('integers', metavar='c', type=int, nargs='+',
help='an integer for the accumulator')
parser.add_argument('--sum', dest='accumulate', action='store_const',
const=sum, default=max,
help='sum the integers (default: find the max)')
args = parser.parse_args(['--sum', '7', '-1', '42'])
print(args.accumulate(args.integers))
This Python code is a basic script that utilizes the argparse module to create a command-line interface for a script that performs either sum or maximum operation on a list of integers. Here is an explanation of the code: 1. Import the argparse module, which is used to parse command-line arguments. 2. Create an ArgumentParser object called `parser` with a description of what the script does. 3. Add two arguments to the parser: - `integers`: An argument that takes one or more integer values. The `nargs='+'` specifies that multiple integer arguments can be provided. - `--sum`: An optional argument that determines whether to sum or find the maximum of the integers. If this argument is passed, the `accumulate` attribute of args will be set to the `sum` function; otherwise, it will default to the `max` function. 4. Parse the command-line arguments. In this case, the script is being tested with the arguments `--sum 7 -1 42`. These arguments would be stored in the `args` variable. 5. Finally, print the result of applying the `accumulate` function (either `sum` or `max`) on the list of integers provided in the command line. In this case, it will print the sum of the integers: `7 + (-1) + 42 = 48`. When you run this script with the provided command-line arguments, it will output the sum of the integers passed as arguments.