'(internal) Unjelly an instance.
Called to handle the deprecated I{instance} token.
@param rest: The s-expression representing the instance.
@return: The unjellied instance.'

def _unjelly_instance(self, rest):

    warnings.warn_explicit('Unjelly    support    for    the    instance    atom    is    deprecated    since    Twisted    15.0.0.        Upgrade    peer    for    modern    instance    support.', category=DeprecationWarning, filename='', lineno=0)
    clz = self.unjelly(rest[0])
    if ((not _PY3) and (type(clz) is not _OldStyleClass)):
        raise InsecureJelly("Legacy    'instance'    found    with    new-style    class")
    return self._genericUnjelly(clz, rest[1])
