Fix MultiEmailField to use validate_email for validation

- Legacy-Id: 6835

ietf/utils/fields.py

@@ -1,6 +1,5 @@
 from django import forms
-from django.forms.util import ValidationError
-from django.core.validators import email_re
+from django.core.validators import validate_email, ValidationError
 
 
 class MultiEmailField(forms.CharField):
@@ -8,15 +7,17 @@ class MultiEmailField(forms.CharField):
 
     def clean(self, value):
         super(MultiEmailField, self).clean(value)
-        if value:
-            if value.endswith(','):
-                value = value[:-1]
-            emails = map(unicode.strip, value.split(','))
-        else:
+        if not value:
             return value
 
+        if value.endswith(','):
+            value = value[:-1]
+        emails = [v.strip() for v in value.split(',') if v.strip()]
+
         for email in emails:
-            if not email_re.match(email):
+            try:
+                validate_email(email)
+            except ValidationError:
                 raise ValidationError("This is not a valid comma separated email list.")
 
         return value