title: Formatting ampersand adds unexpected characters
body: <p>Using <a href="https://github.com/sunscrapers/djoser" rel="nofollow noreferrer">Djoser</a> Im trying to generate right url for my frontend. I have to have ampersand in my url string and Djoser do format this url before sending it to my frontend. The url looks like:</p>
  
  <pre><code>https://localhost:4200/activate?id=MjA&amp;token=540-cad5f834d5508ebdd78e
  </code></pre>
  
  <p>But the final result that I get looks like <strong>note "amp;" after &amp;</strong>:</p>
  
  <pre><code>http://localhost:4200/activate?id=MjE&amp;amp;token=541-c0437e0afd6261fd4833
  </code></pre>
  
  <p>I tried following solutions but none of them works <code>(\u0026, {\u0026}, {\u0026:c}, &amp;&amp;)</code>:</p>
  
  <pre><code>print("https://localhost:4200/activate?id={uid}\u0026token={token}".format(uid="MjA", token="540-cad5f834d5508ebdd78e"))
  print("https://localhost:4200/activate?id={uid}{\u0026}token={token}".format(uid="MjA", token="540-cad5f834d5508ebdd78e")) &lt;-- returns KeyError: '&amp;'
  print("https://localhost:4200/activate?id={uid}{\u0026:c}token={token}".format(uid="MjA", token="540-cad5f834d5508ebdd78e")) &lt;-- returns KeyError: '&amp;'
  </code></pre>
  
  <p><strong>NOTE:</strong> I can't directly change code in <code>format()</code> part, this will be handled by Djoser. The part that I can pass is actually only assign the string value to activation url like there: <code>'ACTIVATION_URL': 'activate?id={uid}{\u0026:c}token={token}',</code> So I have to write my solution in this string.</p>
  
  <p><strong>NOTE2:</strong> I tried it in jupiter, there all works fine, I get the right url when I do it this way: </p>
  
  <pre><code>print("https://localhost:4200/activate?id={uid}\u0026token={token}".format(uid="MjA", token="540-cad5f834d5508ebdd78e"))
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/CbAL7.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/CbAL7.png" alt="enter image description here"></a></p>
  
  <p>Directly adding <code>&amp;</code> returns to frontend same url with <code>amp;</code> behind <code>&amp;</code></p>
  
  <p><strong>UPDATE</strong>
  Djoser template overwriting</p>
  
  <pre><code>TEMPLATES = [
      {
          'BACKEND': 'django.template.backends.django.DjangoTemplates',
          'DIRS': [os.path.join(BASE_DIR, 'templates')],
          'APP_DIRS': True,
          ...
      },
  ]
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/zzeLj.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/zzeLj.png" alt="enter image description here"></a></p>