pyodbc - parameters in group/order clause - Limitation?

Question

So I'm trying to write a SQL query with parameters in the group by clause and have pyodbc execute it; I have the following schema as such:

http://sqlfiddle.com/#!18/4e7bb7/2

In case sqlfiddle fails,

CREATE TABLE Persons (
    Personid int IDENTITY(1,1) PRIMARY KEY,
    Name varchar(255) NOT NULL,
    Birthday datetime
);

INSERT INTO PERSONS (NAME, BIRTHDAY)
VALUES
('a','20220101'),
('b','20220102'),
('c','20220103'),
('d','20220104'),
('e','20220105'),
('f','20220106'),
('g','20220108'),
('h','20220110'),
('i','20220111'),
('j','20220112'),
('k','20220113'),
('l','20220114'),
('m','20220115')

and I have the following query as an example, which is valid SQL:

select
  COUNT(*)
  ,dateadd(week, datediff(week,0, birthday), 0)
 from Persons

group by 
dateadd(week, datediff(week,0, birthday), 0)
order by
dateadd(week, datediff(week,0, birthday), 0)

This query will group the users' birthdays by week. This is simply a contrived example. I have real data that is similar to this.

I'm trying to write a python function where it would grab the data and group them by week. I want this function to be able to decide what day of the week is the start of the week. I have the following function:

import pyodbc
def TestSQLServerDB2(dayOfWeekStart=0):
    """Tests the query.

    :param: dayOfWeekStart: Int. 0 = Monday, 1 = Tuesday, ... 6 = Saturday
    """

    hostname = 'DESKTOPHOST'
    database_instance = "test"
    db_conn = pyodbc.connect('Trusted_Connection=yes;' + r"DRIVER=" + "{SQL SERVER}" +
                    ";SERVER=" + hostname + ";DATABASE=" +
                    database_instance + ";")


    targetWeekday = dayOfWeekStart % 7

    sql = '''
        select
        COUNT(*)
        ,dateadd(week, datediff(week,0, birthday), ?)
        from Persons

        group by 
            dateadd(week, datediff(week,0, birthday), ?)
        order by
            dateadd(week, datediff(week,0, birthday), ?)
    '''

    params = (targetWeekday ,targetWeekday ,targetWeekday )
    
    cur = db_conn.cursor()
    cur.execute(sql, params)
    
    print(cur.fetchall())

Running this function will produce the following error:

pyodbc.ProgrammingError: ('42000', "[42000] [Microsoft][ODBC SQL Server Driver][SQL Server]Column 'Persons.Birthday' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause. (8120) (SQLExecDirectW); [42000] [Microsoft][ODBC SQL Server Driver][SQL Server]Statement(s) could not be prepared. (8180)")

It's trivial enough for me to do a string replace on the SQL query prior to executing, and I won't face any issues; what I want to know is whether SQL parameterized statements are just limited to value comparisons in the WHERE clause basically or not? Is this an intended design?

Thanks