title: Django models : Field 'id' expected a number but got 'Students'
body: <p>I'm trying to filter objects based on a foreign key and I'm getting that error. When I use int( id of categories) the code below works. How can I make it work for strings?</p>
  <p>models.py:</p>
  <pre><code>from django.db import models
  
  # Create your models here.
  class Category(models.Model):
      category_name=models.CharField(max_length=40)
  
      def __str__(self):
          return self.category_name
  
  class dash(models.Model):
      title=models.CharField(max_length=40)
      card_pic=models.ImageField(upload_to=&quot;dash_pics/&quot;)
      embed_tag=models.TextField()
      category=models.ForeignKey(Category,on_delete=models.CASCADE)
      objects = models.Manager()
      def __str__(self):
          return self.title
  </code></pre>
  <p>views.py:</p>
  <pre><code>def students(request):
      stu_dashboards = models.dash.objects.filter(category='Students')
      return render(request,'dashboards/students.html',{'dashboards':stu_dashboards})
  </code></pre>