Merge pull request #2190 from caumons/datetimefield-wtforms3

Fixed DateTimeField format compatibility with WTForms 3.0. Fixes #2189

Author: mrjoes

flask_admin/form/fields.py

@@ -36,9 +36,8 @@ def __init__(self, label=None, validators=None, format=None, **kwargs):
             :param kwargs:
                 Any additional parameters
         """
-        super(DateTimeField, self).__init__(label, validators, **kwargs)
-
-        self.format = format or '%Y-%m-%d %H:%M:%S'
+        super(DateTimeField, self).__init__(
+            label, validators, format or '%Y-%m-%d %H:%M:%S', **kwargs)
 
 
 class TimeField(fields.Field):