Lets follow the Assert style to test the starwars people api as shown below
var chai = require('chai')
pm.test("Structure Testing", () => {
const responseBodyInJson = pm.response.json();
// checking if the response exists
chai.assert.exists(responseBodyInJson, "Response should not be null or undefined");
chai.assert.isObject(responseBodyInJson, "Response should be an object");
chai.assert.isString(responseBodyInJson.name, "Name should be a string");
// try to write the type is string for string fields
chai.assert.isArray(responseBodyInJson.films, "films should be an array");
});