def clean_email(self):
     """
     Validates the supplied email address is unique for the site.
     """
     email = self.cleaned_data["email"]
     if backend.user_filter(filterstring=email):
         raise forms.ValidationError(self.error_messages['email_dup'])
     return email
 def clean_email(self):
     """
     Validates that an active user exists with the given email address.
     """
     email = self.cleaned_data["email"]
     self.users_cache = backend.user_filter(filterstring=email)
     if not len(self.users_cache):
         raise forms.ValidationError(self.error_messages['unknown'])
     return email