Function promisify

promisify<T>(
fn: (callback: (err: Error, result?: T) => void) => void,
): Promise<T>
Converts a callback-based function to a Promise-based function.
Type Parameters
- T
Parameters
- fn: (callback: (err: Error, result?: T) => void) => void
  The callback-based function to convert.
Returns Promise<T>
A Promise-based version of the function.