trapping a MySql warning

In my python script I would like to trap a "Data truncated for column 'xxx'" warning durnig my query using MySql.

I saw some posts suggesting the code below, but it doesn' work.

Do you know if some specific module must be imported or if some option/flag should be called before using this code?

Thanks all

Afeg

import MySQLdb
try:
    cursor.execute(some_statement)
    # code steps always here: No Warning is trapped
    # by the code below
except MySQLdb.Warning, e:
    # handle warnings, if the cursor you're using raises them
except Warning, e:
    # handle warnings, if the cursor you're using raises them