old_contents: from django.core.exceptions import MultipleObjectsReturned, ObjectDoesNotExist
  
  from social_auth.models import UserSocialAuth
  from social_auth.exceptions import AuthException
  
  
  def associate_by_email(details, user=None, *args, **kwargs):
      """Return user entry with same email address as one returned on details."""
      if user:
          return None
  
      email = details.get('email')
  
      if email:
          # try to associate accounts registered with the same email address,
          # only if it's a single object. AuthException is raised if multiple
          # objects are returned
          # Allow case-insensitive match, since real-world email address is case-insensitive
          try:
              return {'user': UserSocialAuth.get_user_by_email(email__iexact=email)}
          except MultipleObjectsReturned:
              raise AuthException(kwargs['backend'], 'Not unique email address.')
          except ObjectDoesNotExist:
              pass
  
new_contents: from django.core.exceptions import MultipleObjectsReturned, ObjectDoesNotExist
  
  from social_auth.models import UserSocialAuth
  from social_auth.exceptions import AuthException
  
  
  def associate_by_email(details, user=None, *args, **kwargs):
      """Return user entry with same email address as one returned on details."""
      if user:
          return None
  
      email = details.get('email')
  
      if email:
          # try to associate accounts registered with the same email address,
          # only if it's a single object. AuthException is raised if multiple
          # objects are returned
          # Allow case-insensitive match, since real-world email address is case-insensitive
          try:
              return {'user': UserSocialAuth.get_user_by_email(email=email)}
          except MultipleObjectsReturned:
              raise AuthException(kwargs['backend'], 'Not unique email address.')
          except ObjectDoesNotExist:
              pass
  
subject: Fix __iexact call. Closes #617