title: type object 'datetime.timezone' has no attribute 'now'
body: <p>This line of code is receiving an AttributeError:
  <code>now = timezone.now()</code></p>
  <p>I can't figure out why. I am correctly importing the package as follows:
  <code>from django.utils import timezone</code></p>
  <p>But it is still throwing:</p>
  <p><code>Attribute Error: type object 'datetime.timezone' has no attribute 'now'</code></p>
  <p>Model</p>
  <pre><code>class Donaci(models.Model):
      creation_date = models.DateTimeField(auto_now_add=True, blank=True)
      message = models.CharField(max_length=300, null=True, blank=True)
  
      def whenpublished(self):
          now = timezone.now()
          
          diff = now - self.creation_date
  
          if diff.days == 0 and diff.seconds &gt;= 0 and diff.seconds &lt; 60:
              seconds= diff.seconds
              
              if seconds == 1:
                  return str(seconds) +  &quot;second ago&quot;
              
              else:
                  return str(seconds) + &quot; seconds ago&quot;
  </code></pre>
  <p>Imports</p>
  <pre><code>from django.contrib.auth.models import AbstractUser
  from django.contrib.auth import settings
  from django.utils import timezone
  from django.db import models
  from datetime import *
  </code></pre>