If Else Not Checking Both Of The Conditions In Python

i want new column ['pred_n'] to be created based on certain condition, condition is as follows: if year is less than or equal to current year & month is less than current month

Solution 1:

You are currently using the bitwise operators | and &, rather than the logical operators orand and. Presumably you really want something like:

now = datetime.now()
if (dfyz['year_x'] < now.year or        
    dfyz['year_x'] == now.year and dfyz['mon'] < now.month
):
    ...

(Its not great practice to keep calling now several times ... each of your calls is potentially returning a different value for now)