Frappe call if else statement

1

I want to get a value in frappe call.But when there is no value is occured i want insert a document and while value is present i want update the value. when if is working and the else is not working .any one plz help me solve the issue

2

to be more specific, which business case, via js or python script, or hooked python code? what you have tried, what is the current and expected result?