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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 main_group(ctx, verbose, quiet, access_token, config):
 """This is the command line interface to Mapbox web services. Mapbox web services require an access token. Your token is shown on the https://www.mapbox.com/studio/account/tokens/ page when you are logged in. The token can be provided on the command line as an environment variable named MAPBOX_ACCESS_TOKEN (higher precedence) or MapboxAccessToken (lower precedence). \b $ export MAPBOX_ACCESS_TOKEN=MY_TOKEN or in a config file \b ; configuration file mapbox.ini [mapbox] access-token = MY_TOKEN The OS-dependent default config file path is something like \b ~/Library/Application Support/mapbox/mapbox.ini ~/.config/mapbox/mapbox.ini ~/.mapbox/mapbox.ini """

    ctx.obj = {}
    config = config or os.path.join(click.get_app_dir('mapbox'), 'mapbox.ini')
    cfg = read_config(config)
    if cfg:
        ctx.obj['config_file'] = config
    ctx.obj['cfg'] = cfg
    ctx.default_map = cfg

    verbosity = (os.environ.get('MAPBOX_VERBOSE') or
                 ctx.lookup_default('mapbox.verbosity') or 0)
    if verbose or quiet:
        verbosity = verbose - quiet
    verbosity = int(verbosity)
    configure_logging(verbosity)

    access_token = (access_token or os.environ.get('MAPBOX_ACCESS_TOKEN') or
                    os.environ.get('MapboxAccessToken') or
                    ctx.lookup_default('mapbox.access-token'))

    ctx.obj['verbosity'] = verbosity
    ctx.obj['access_token'] = access_token