TypeError: Cannot set property 'get_id' of undefined

[akashkumar2296]

/Users/kumarak/Documents/reaxt/Umich_schedule_planner/Ani-React-Theme/node_modules/pdf2json/pdfparser.js:96 this.get_id = () => _id; ^ TypeError: Cannot set property 'get_id' of undefined at PdfParser (/Users/kumarak/Documents/reaxt/Umich_schedule_planner/Ani-React-Theme/node_modules/pdf2json/pdfparser.js:96:21) at Object.<anonymous> (/Users/kumarak/Documents/reaxt/Umich_schedule_planner/Ani-React-Theme/build/webpack:/server.js:80:9) at __webpack_require__ (/Users/kumarak/Documents/reaxt/Umich_schedule_planner/Ani-React-Theme/build/webpack:/webpack/bootstrap 6116393c83e95f4fdfa2:25:1) at /Users/kumarak/Documents/reaxt/Umich_schedule_planner/Ani-React-Theme/build/webpack:/webpack/bootstrap 6116393c83e95f4fdfa2:60:1 at Object.<anonymous> (/Users/kumarak/Documents/reaxt/Umich_schedule_planner/Ani-React-Theme/build/webpack:/webpack/bootstrap 6116393c83e95f4fdfa2:60:1) at Module._compile (module.js:570:32) at Object.Module._extensions..js (module.js:579:10) at Module.load (module.js:487:32) at tryModuleLoad (module.js:446:12) at Function.Module._load (module.js:438:3) at Module.runMain (module.js:604:10) at run (bootstrap_node.js:389:7) at startup (bootstrap_node.js:149:9) at bootstrap_node.js:502:3 /Users/kumarak/Documents/reaxt/Umich_schedule_planner/Ani-React-Theme/tools/runServer.js:71 throw new Error(Server terminated unexpectedly with code: ${code} signal: ${signal});

Not really sure why this error keeps popping up?