def _get_new_session_key(self):
        # Todo: move to 0-9a-z charset in 1.5
        hex_chars = '1234567890abcdef'
        # session_key should not be case sensitive because some backends
        # can store it on case insensitive file systems.
        while True:
            session_key = get_random_string(32, hex_chars)
            if not self.exists(session_key):
                break
        return session_key
Validate a Range value.
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.4/django/contrib/sessions/backends/base.py/SessionBase._get_new_session_key--crossover with--dataset/ETHPy150Open enthought/traitsui/traitsui/editors/csv_list_editor.py/_validate_range_value