avoid 500 when end=null in frequency timespec

larigira/timeform_base.py

@@ -1,13 +1,13 @@
 import logging
 from datetime import datetime
 
-from flask_wtf import Form
 from pytimeparse.timeparse import timeparse
+
+from flask_wtf import Form
+from larigira.formutils import EasyDateTimeField
 from wtforms import (SelectMultipleField, StringField, SubmitField,
                      ValidationError, validators)
 
-from larigira.formutils import EasyDateTimeField
-
 log = logging.getLogger(__name__)
 
 
@@ -84,9 +84,9 @@ class FrequencyAlarmForm(Form):
     def populate_from_timespec(self, timespec):
         if "nick" in timespec:
             self.nick.data = timespec["nick"]
-        if "start" in timespec:
+        if timespec.get("start"):
             self.start.data = datetime.fromtimestamp(timespec["start"])
-        if "end" in timespec:
+        if timespec.get("end"):
             self.end.data = datetime.fromtimestamp(timespec["end"])
         if "weekdays" in timespec:
             self.weekdays.data = timespec["weekdays"]