title: 'Q' object has no attribute 'split' - Django
body: <p>I have a Model: </p>
  
  <pre><code>class Authors(models.Model):
     name = models.TextField()
     person = models.ForeignKey(Person)
  </code></pre>
  
  <p>and query: </p>
  
  <pre><code>authors = Author.objects.filter(
                                  (Q(name__iregex=r"\y{0}\y".format(s1)),
                                  ~Q(name__iregex=r"\y{0}\y".format(s2))
                                  ),
                                  person=None).order_by('-id')
  </code></pre>
  
  <p>I am getting the error: </p>
  
  <pre><code>'Q' object has no attribute 'split'
  </code></pre>
  
  <p>why is this? i am not using <code>split()</code> though.. the line of error is in this query line. </p>