text: 'use strict';
  
  const obj1 = {
    a: 'a',
    b: 'b',
    text: 'this text exists only to check getter',
    sum3: {},
    simpleOperations: {},
    multiply: {},
    divide: {}
  }
  
  // implement mixin logable();
  
  const mixin = (obj) => (
    obj['get'] = key => obj[key],
    obj['set'] = (key, value) => obj[key] = value
  );
  
  mixin(obj1);
  console.log(obj1.get('text'));
  obj1.set('c', 'd');
  console.log(obj1);
  