Thanks for you answer Dan,
I found the reason why my script doesn't work, it's because Arcgis double my apostrophe in the attribute.
So i'm parsing this string to definition query in my script.
"Arrondisse"='Baie-d'Urfé'
and when I open the attributes tables my table is empty.
When i'm doing an selection by attribute and I double the apostrophe, it's works.
"Arrondisse" = 'Baie-d''Urfé'
but I can't figured out how to write it and make it works in my script.
if lyr.name == "Ecoles":
lyr.definitionQuery = '"Arrondisse"' + "=" + "'" + arrondissement + "'"
if lyr.definitionQuery == """"Arrondisse"=u'Baie-d'Urfé'""":
lyr.defintionQuery = """"Arrondisse"=u'Baie-d''Urfé'"""
UnicodeWarning: Unicode equal comparison failed to convert both arguments to Unicode - interpreting them as being unequal
if lyr.definitionQuery == """"Arrondisse"=u'Baie-d'Urfé'""":
Thanks