title: django queryset select_related . values() rename key
body: <p>Using python3.4 django 2.0.2</p>
  
  <p>models.py</p>
  
  <pre><code>class Userinfo(models.Model):
  
      useruid = models.BigAutoField(db_column='UserUID', primary_key=True)
  
      useremail = models.CharField(
              db_column='UserEmail', unique=True, max_length=100)
      userpassword = models.CharField(db_column='UserPassword', max_length=128)
  
      passwordsalt = models.CharField(db_column='PasswordSalt', max_length=128)
      userstatus = models.IntegerField(db_column='UserStatus', default=0)
      username = models.CharField(
          db_column='UserName', max_length=100, default=0)
      class Meta:
          managed = False
          db_table = 'userinfo'
  
  class Postinfo(models.model):
      postuid = models.BigAutoField(db_column='PostUID', primary_key=True)
      content = content = models.TextField(db_column='Content')
      useruid = models.ForeignKey(
      Userinfo, db_column='UserUID', on_delete=models.CASCADE)
  
      class Meta:
           managed = False
           db_table = 'postinfo'
  </code></pre>
  
  <p>queryset</p>
  
  <pre><code>postquery = models.Postinfo.objects.all().select_related("useruid").order_by(
                  '-postuid')
  </code></pre>
  
  <p>postquery is </p>
  
  <pre><code>&lt;QuerySet [{'content': 'test','postuid': 1, 'useruid_id': 1},OtherPosts...&gt;
  </code></pre>
  
  <p>and </p>
  
  <pre><code>userinfoquery = postquery.values("useruid_id__username","useruid_id__userstatus","useruid_id")
  </code></pre>
  
  <p>userinfoquery is</p>
  
  <pre><code> &lt;QuerySet [{'useruid_id__username': 'firstuser','useruid_id__userstatus': 0, 'useruid_id': 1},OtherUsers...&gt;
  </code></pre>
  
  <p>i want useruid_id__username - > username</p>
  
  <p>useruid_id__userstatus -> userstatus</p>
  
  <p>useruid_id - > useruid</p>
  
  <p>i tried this </p>
  
  <pre><code>userinfoquery = postquery.values(
                  useruid="useruid_id", username="useruid_id__username", userstatus="useruid_id__userstatus")
  </code></pre>
  
  <p>this code raise exception</p>
  
  <pre><code>QuerySet.annotate() received non-expression(s): useruid_id, useruid_id__uesrname, useruid_id__userstatus.
  </code></pre>
  
  <p>how can remove useruid_id__ </p>