npm run build command is not working

[yokotoka]

$ npm run build

> ccc_filter@1.0.0 build /home/yokotoka/p/artedem/ccc/ccc_filter
> NODE_ENV=production webpack --progress --colors -p && npm run flask-static-digest

Invalid configuration object. Webpack has been initialised using a configuration object that does not match the API schema.
 - configuration.devtool should be one of these:
   string | false
   -> A developer tool to enhance debugging.
   Details:
    * configuration.devtool should be a string.
    * configuration.devtool should be false
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! ccc_filter@1.0.0 build: `NODE_ENV=production webpack --progress --colors -p && npm run flask-static-digest`
npm ERR! Exit status 1
npm ERR! 
npm ERR! Failed at the ccc_filter@1.0.0 build script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     /home/yokotoka/.npm/_logs/2019-12-07T20_08_49_980Z-debug.log

[yokotoka]

If you change devtool: debug ? "eval-source-map" : null, to devtool: debug ? "eval-source-map" : false, this issue will be fixed.