How to pass parameters to SQL query using python

I have a list of existing tables in database, I need to update existing tables with CSV files. So what I have done is:

1. I have created temp tables in database and I have inserted the values from CSV files to the temp tables in database.

2. Then I have made two lists, one list consists of existing tables and other list consists of temp table.

3. I created my temp tables with prefixed existing tables names ending with temp eg. tablenametemp, so that I can match with existing tables.

4. Once I found the match then I will update the existing tables with the temp tables with matching primary keys.

5. If the primary key already exists the I will update the existing records ELSE I will insert it as a new record to the table

6. Once all done temp tables are removed here is the code which I have done.

Here is my code:

for a in list_table:
    if a+'temp' in list_temp:
        pk = engine.execute('''
                                    SELECT C.COLUMN_NAME 
                                    FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS T  
                                    JOIN INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE C ON C.CONSTRAINT_NAME = T.CONSTRAINT_NAME  
                                    WHERE C.TABLE_NAME = ? 
                                    AND T.CONSTRAINT_TYPE = 'PRIMARY KEY'  ''',a)


        pk_temp = engine.execute('''
                                    SELECT C.COLUMN_NAME 
                                    FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS T  
                                    JOIN INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE C ON C.CONSTRAINT_NAME = T.CONSTRAINT_NAME  
                                    WHERE C.TABLE_NAME = ? 
                                    AND T.CONSTRAINT_TYPE = 'PRIMARY KEY'  ''',a+"temp")
        col = engine.execute('''
                                    SELECT column_name FROM INFORMATION_SCHEMA. COLUMNS
                                    WHERE TABLE_NAME = ?  ''',a)
        col_temp = engine.execute('''
                                    SELECT column_name FROM INFORMATION_SCHEMA. COLUMNS
                                    WHERE TABLE_NAME = ?  ''',a+"temp")
        query_params = { 'table' : str(a),
                         'table_temp' : str(a+'temp'),
                         'primary_key' : str(pk),
                         'primary_key_temp' : str(pk_temp),
                         'columns' : str(col),
                         'columns_temp' : str(col_temp),
                         'columns1': str(col),
                         'columns_temp2': str(col_temp)
        }

        sql_merge = text("""
        MERGE ? Target
        USING ? AS Source
        ON Source.? = Target.?
        /* new records ('right match') */
        WHEN NOT MATCHED BY Target THEN
        INSERT (?)
        VALUES (Source.?)
        /* matching records ('inner match') */
        WHEN MATCHED THEN
        UPDATE SET
        Target.? = Source.?
        /* deprecated records ('left match') */
        WHEN NOT MATCHED BY Source THEN
        DELETE
        ;
        """ )

        c = engine.execute(sql_merge, params = query_params)
        engine.execute("""DROP TABLE IF EXISTS ? """, a+"temp")

I have tried passing parameters in this way and I get an error like this

COUNT field incorrect or syntax error (0)

Please help me to solve this.