title: Disconnect signals for models and reconnect in django
body: <p>I need make a save with a model but i need disconnect some receivers of the signals  before save it.</p>
  
  <p>I mean,</p>
  
  <p>I have a model:</p>
  
  <pre><code>class MyModel(models.Model):
      ...
  
  def pre_save_model(sender, instance, **kwargs):
      ...
  
  pre_save.connect(pre_save_model, sender=MyModel)
  </code></pre>
  
  <p>and in another place in the code i need something like:</p>
  
  <pre><code>a = MyModel()
  ...
  disconnect_signals_for_model(a)
  a.save()
  ...
  reconnect_signals_for_model(a)
  </code></pre>
  
  <p>Because i need in this case, save the model without execute the function pre_save_model.</p>