Check out example codes for "This syntax requires an imported helper but module 'tslib' cannot be found.". It will help you in understanding the concepts better.

Code Example 1

{
  // ...rest of config
  "compilerOptions": {
    // ...rest of compiler options
    "baseUrl: ".",
    "paths": {
      "tslib" : ["path/to/node_modules/tslib/tslib.d.ts"]
    }
  }
}

Code Example 2

npm install tslib

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