[PYTHON] How to use argparse and the difference between optparse

Previously, I wrote an article as How to use OptParser, but apparently argparse.ArgumentParser is better.

So a note on how to use argparse.ArgumentParser

# -*- coding:utf-8 -*-
from optparse import OptionParser
from argparse import ArgumentParser
 
if __name__ == '__main__':
 
    """Character string to be displayed when a command error occurs"""
    desc = u'{0} [Args] [Options]\nDetailed options -h or --help'.format(__file__)
    # %prog cannot be output
    # usage = u'%prog [Args] [Options]\nDetailed options -h or --help'

    parser = ArgumentParser(description=desc)
    # _parser = OptionParser(usage=usage, version=1.0)
 
    #String
    parser.add_argument(
        '-q', '--query',
        type = str,         #Specify the type of value to receive
        dest = 'query',     #Save destination variable name
        required = True,    #Required item
        help = 'Word to search' # --Statement to display when helping
    )
    # _parser.add_argument(
    #     '-q', '--query',
    #     action = 'store',
    #     type = 'str',               #Specify the type of value to receive
    #     dest = 'download_date',     #Save destination variable name
    #     help = 'Word to search'  # --Statement to display when helping
    # )

    #Numerical value
    parser.add_argument(
        '-w', '--worker',
        type = int,
        dest = 'worker',
        default = 1,
        help = 'Number of multi-processes'
    ) 
    #Boolean value
    parser.add_argument(
        '-b', '--bool',
        action = 'store_true', # store_True puts True in dest(store_There is also false)
        dest = 'bool'
    )
 
    # """Set the default value for each option"""
    # _parser.set_defaults(worker = 1)
 
    """Perspective options"""
    args = parser.parse_args()
    # _options, _args = _parser.parse_args()
 

    """The value specified in the option is args.<Variable name>Can be obtained with"""
    query, worker, bool = args.query, args.worker, args.bool
    # query, worker, bool = _options.query, _options.worker, _options.bool
    if worker > 100
        #When generating an error ↓ Like this
        parser.error('Too many processes')
 
    print args

I don't think optparse and argparse will change that much It seems that various functions have been added to argparse, as the details have changed, but basically this is enough.

reference

http://docs.python.jp/2/library/argparse.html