Pyhton script для дампа и удаления партиции

gistfile1.py

#!/usr/bin/python
# -*- coding: utf-8 -*-
# python 2
# https://wiki.postgresql.org/wiki/Psycopg
import os
from datetime import datetime, time, timedelta, date
import psycopg2
import sys

conn = None
try:
    conn = psycopg2.connect(user='user', password='pas', host='***.com', dbname='dname', port=5432)
    cur = conn.cursor()
    today = date.today()
    month = today.replace(year=today.year - 3, month=today.month, day=today.day)
    month = month.strftime("%Y-%m")

    cur.execute('''select 1 from "myshem"."tagdata_%s";'''% month)
    #dump
    DB_HOST = 'localhost'
    DB_USER = 'user'
    DB_NAME = 'dname'
    BACKUP_PATH = '/backups/tagdata/'

    passFileCmd = 'export PGPASSFILE=/root/.pgpass'
    os.popen(passFileCmd)

    currentBackupName = BACKUP_PATH +  DB_NAME + "_"  + month + ".gz"
    dumpcmd = "pg_dump -t SC_Tag.tagdata_+"+month+" -U " + DB_USER + " -w  " + DB_NAME + " | gzip >> " + currentBackupName
    #C:\Program Files (x86)\EMS\SQL Manager Lite for PostgreSQL\Dump\pg_dump93.exe -h asutpdb.vgok.ru -p 5432 -U asutp -F p -E UTF8 -Z 9 -t """SC_Tag"".""tagdata_2014-06""" -v -f "D:\postgres\pg\my.gzip" DB_ASUTP_2
    retval = os.popen(dumpcmd).read()
    #dump

except psycopg2.DatabaseError, e:
    print 'Error %s' % e
    sys.exit(1)

finally:

    if conn:
        conn.close()