'Remove C{key} from C{_createdKey}.
@param key: a key object to be freed; i.e. removed from
C{_createdKeys}.
@raises ValueError: If C{key} is not in C{_createdKeys} and thus not
created by us.'

def EC_KEY_free(self, key):

    try:
        self._createdKeys.remove(key)
    except KeyError:
        raise ValueError('Unallocated    EC    key    attempted    to    free.')
