def     NewD(user_kod,contragent,tema,text):
    user_kod = user_kod.encode("utf-8")
    contragent = contragent.encode("utf-8")
    tema = tema.encode("utf-8")
    text = text.encode("utf-8")
    cursor = connections['default'].cursor()
    cursor.execute("SELECT t_NewD('%s','%s','%s','%s');" % (user_kod,contragent,tema,text))
    transaction.commit_unless_managed()
    data = cursor.fetchone()
    return data[0]

>>> NewD('','%','%','%')
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/opt/kis/kis/lib/contract.py", line 81, in NewD
    cursor.execute("SELECT t_NewD('%s','%s','%s','%s');" % (user_kod,contragent,tema,text))
  File "/usr/local/lib/python2.7/dist-packages/django/db/backends/util.py", line 41, in execute
    return self.cursor.execute(sql, params)
  File "/usr/local/lib/python2.7/dist-packages/django/db/backends/postgresql_psycopg2/base.py", line 54, in execute
    return self.cursor.execute(query, args)
IndexError: tuple index out of range