TypeError: iterable argument required

Sat Apr 2 12:26:18 EDT 2011

Hello, after inserting this line if "@" in mail and comment not in
("Σχολιάστε ή ρωτήστε με σχετικά....", ""):
iam getting the following error which i dont understand
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163 # insert guest comments into database if form was
submitted
 164 if "@" in mail and comment not in ("Σχολιάστε ή ρωτήστε
με σχετικά....", ""):
 165 try:
 166 cursor.execute( '''INSERT INTO
users(mail, comment) VALUES(%s, %s)''', (mail, comment) )
mail = None, comment = None
TypeError: iterable argument required
 args = ('iterable argument required',)
**************************************************************
can you help please?