how to use the sumby function from the lodash library in typescript

To use the sumBy function from lodash library in TypeScript, you can first install the @types/lodash package using npm:

npm install @types/lodash
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Then, you can import the sumBy function from lodash in your TypeScript file and use it as follows:

index.ts
import { sumBy } from 'lodash';

const data = [
  { name: 'John', age: 25, score: 80 },
  { name: 'Jane', age: 30, score: 90 },
  { name: 'Bob', age: 40, score: 70 },
];

const totalScore = sumBy(data, 'score');
console.log('Total Score:', totalScore); // Output: Total Score: 240
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In the example above, we imported the sumBy function from lodash and used it to calculate the total score of the objects in the data array. The second argument of the sumBy function specifies the property to be summed up in each object (in this case, it's the score property). The result is stored in the totalScore variable and then printed to the console.