Create Empty Dataframe of Date Sequence

from pyspark.sql.functions import explode, to_date, lit

df = (
    spark
    .createDataFrame([{'date':1}])
    .select(
        explode(sequence(
            to_date(lit('2021-01-01')), # start
            to_date(lit(date.today())), # stop
            expr("INTERVAL 1 WEEK")     # step
        )).alias('calendar_date')
    )
)