title: Does 'default=...' in Django model fields set 'blank=True' by default?
body: <p>I have a question for the Django model field when applying the <code>default</code> setting. My problem is as follows:</p>
  
  <pre><code># Model description
  class aa(models.Model):
      a = models.FloatField(default=1)
      b = models.FloatField()
  </code></pre>
  
  <p>When inserting an entry into the database, I apply the following functions to do the validation without any error:</p>
  
  <pre><code>data = {'b': 1.1} # Just for demo...
  p = aa(**data)
  p.full_clean()
  p.save()
  </code></pre>
  
  <p>Here is the problem, is the case that when I set the <code>default</code> value for a field, the <code>blank</code> is automatically set to <code>True</code>?</p>
  
  <p>P.S. I know what are the differences between <code>null</code> and <code>blank</code>, I just want to figure out the issues related to the <code>default</code>.</p>