How to retrieve millions of rows from an oracle DB to a flat file using Python

import pandas as pd
import cx_Oracle
import datetime
import os

try:
    chunk_size = 1000000
    batch_no = 1
    start_time = datetime.datetime.now()
    print("Program Start Time:: ", start_time)
    dsn_tns = cx_Oracle.makedsn('HOSTNAME', 'PORT', service_name=r'SERVICE_NAME')
    conn = cx_Oracle.connect(user=r'USERNAME', password=r'PASSWORD', dsn=dsn_tns)
    query = """Select /*+ parallel(a,16) */ * from SCHEMA.TABLE_NAME a"""
    for chunk in pd.read_sql_query(query, con=conn, chunksize=chunk_size):
        chunk.to_csv(r'<path>\Test_Sample_Output_20230303_'+str(batch_no)+'.txt', sep='|',
                   quotechar='"', escapechar='\\', index=False, encoding='utf-8-sig')
        batch_no += 1
    end_time = datetime.datetime.now()
    print("Program End Time:: ", end_time)
    Exact_time_Taken = end_time - start_time
    print("Exact Time Taken :: ", Exact_time_Taken)

except cx_Oracle.DatabaseError as e:
    print("There is a problem with Oracle", e)