def validator(self, node, cstruct):
    sort = cstruct['sort']
    search_after = cstruct.get('search_after', None)
    if search_after:
        if ((sort in ['updated', 'created']) and (not self._date_is_parsable(search_after))):
            raise colander.Invalid(node, "search_after must be a parsable date in the form\n                    yyyy-MM-dd'T'HH:mm:ss.SSX\n                    or time in miliseconds since the epoch.")
        cstruct['offset'] = 0
def validator(self, node, cstruct):
    sort = cstruct['sort']
    search_after = cstruct.get('search_after', None)
    if search_after:
        if ((sort in ['updated', 'created']) and (not self._date_is_parsable(search_after))):
            raise colander.Invalid(node, "search_after must be a parsable date in the form\n                    yyyy-MM-dd'T'HH:mm:ss.SSX\n                    or time in miliseconds since the epoch.")
        cstruct['offset'] = 0