How to add TypeScript prop type definitions to an existing React component

react-some-component.d.ts

import * as React from 'react';

declare class SomeReactComponent extends React.Component<SomeReactComponentProps, any> {}

interface SomeReactComponentProps {
  className?: string;
  toggle?: boolean;
  name: string;
  size?: 'lg' | '2x' | '3x' | '4x' | '5x';
}

declare var SomeReactComponentType: typeof SomeReactComponent;
export = SomeReactComponentType;