Typing a string index

Question

I have some data.

const people = {
    john : {
     //somedata
    },
   peter : {
     //somedata
    },
   mark: {
     //somedata
    }
}

and I type it

  export type People = {
     [key : string]: Person
   }


 export interface Person {
   age: number;
   profession: string;
 // some more data

   }

The error is TS7053: Element implicitly has an 'any' type because expression of type 'string' can't be used to index type. I would not usually use a string as the key but in this case it is necessary and typescript does not like it even though I have told it to expect a string.

Any idea how I can type this properly?