Add Column from list of integers PySpark

I am trying to add a column to my PySpark DataFrame of a list of integers. It was originally a date time object that I extracted the date from:

date = []

for i in range(count):
    if i+1 == count:
        date.append((datetime.date.today() - dates[i][0]).days)
        
    elif dates[i][0] == dates[i+1][0] and product[i][0] == product[i+1][0]:
        date.append((dates[i+1][0] - dates[i][0]).days)
    else:
        date.append((datetime.date.today() - dates[i][0]).days)

I then tried to add date as as a new column like this:

df = df.withColumn("Date Difference", date)

and get this error: AssertionError: col should be Column

How do I add this column of days without getting the error? Thank you!

source https://stackoverflow.com/questions/69352170/add-column-from-list-of-integers-pyspark