'Is Null' in Python

[HemantAngarkar2]

I am trying to use field calculator where values will be taken from one field of two fields with if condition. If first field is null then value will be taken from second field. In VB there is 'is Null' keyword. What is there in Python?

[DanPatterson_Retired]

Try this

[JasonScheirer · Accepted solution]

You can use

value is None

For example, in your expression you can do

!field1! if not !field1! is None else !field2!

alternately just do

!field1! or !field2!

[IanMurray]

Take a look at this thread

arcgis 10.0 - How do you test for a NULL string field in the Field Calculator with Python? - Geograp...‌