code: def case_study_social_link_linkedin(value):
      
  
      parsed = parse.urlparse(value.lower())
      if not parsed.netloc.endswith('linkedin.com'):
          raise ValidationError(MESSAGE_NOT_LINKEDIN)
docs: Confirms that the social media url is pointed at the correct domain.
  
      Args:
          value (string): The url to check.
  
      Raises:
          django.forms.ValidationError