':py:class:`PKey` takes no arguments and returns a new :py:class:`PKey` instance.'

def test_construction(self):

    self.assertRaises(TypeError, PKey, None)
    key = PKey()
    self.assertTrue(isinstance(key, PKeyType), ('%r    is    of    type    %r,    should    be    %r' % (key, type(key), PKeyType)))
