fetch is not defined error in React Native

Is this a code style error? if so, you can disable that line according to your code styling library

If not, what you need to import to make it work is:

import "isomorphic-fetch";

It might be better to add it in your .eslintrc config instead since the Fetch API is already included in React Native.

Details: https://github.com/eslint/eslint/issues/4015#issuecomment-301920490