The required argument weekday is a number between 1 and 7 that represent a day of the week. The abbreviate argument is optional. It accepts a boolean value, that indicates if the month name is to be abbreviated. If omitted, the default is False, which means that the month name is not abbreviated. The firstweekday argument is also optional. It determines what day is to be the first day of the week. The following is a list of valid parameters for firstweekday.