title: console.log is omitting some key pairs?
body: <p>I'm debugging a NodeJS app where <code>mongodb</code> is being used.</p>
  
  <p>When I <code>console.log</code> keys of a JS object (say <code>booking</code>) using <code>console.log( Object.keys(booking) )</code> statement, it prints:</p>
  
  <pre><code>[
    '$__',     'isNew',
    'errors',  '_doc',
    '$locals', '$op',
    '$init'
  ]
  </code></pre>
  
  <p>But When I directly print the same object using <code>console.log(booking)</code> statement, it prints:</p>
  
  <pre><code>{
    _id: 5eb4fef797bf1e29986e333f,
    user: 5eb413c78a84bc63f0ef83d4,
    event: {
      _id: 5eb4182c45d25b4c981a21ce,
      title: 'Test Event',
      description: 'bla bla bla',
      price: 99.99,
      date: 'Wed Jan 01 2020 05:45:00 GMT+0545',
      creator: 5eb413c78a84bc63f0ef83d4,
      __v: 0
    },
    createdAt: 2020-05-08T06:40:55.905Z,
    updatedAt: 2020-05-08T06:40:55.905Z,
    __v: 0
  }
  </code></pre>
  
  <p>Now if you notice, some keys are missing both times I do <code>console.log</code>. I have no idea what the hell is going on. WHY is that happening?</p>
  
  <p>I'm also using <code>mongoose</code> models. My code is like this:</p>
  
  <pre><code>Booking.findById({_id: args.bookingID}).populate('event').then(booking =&gt; {
      console.log( booking )
      console.log( Object.keys(booking) )
  });
  </code></pre>
  
  <p>Please ask if you need anymore information.</p>
  
  <p>Any help will be appreciated :)</p>