unexpected Index loaded: pd.Index([10, 20, None], name="x")

pidx = pd.Index([10, 20, 15, 30, 45, None], name="x")
psidx = ps.Index(pidx)
self.assert_eq(psidx.astype(str), pidx.astype(str))

[left pandas on spark]: Index(['10.0', '20.0', '15.0', '30.0', '45.0', 'nan'], dtype='object', name='x')
[right pandas]: Index(['10', '20', '15', '30', '45', 'None'], dtype='object', name='x')

The index is loaded as float64, so the follow step like astype would be diff with pandas

[1] https://github.com/apache/spark/blob/bcc595c112a23d8e3024ace50f0dbc7eab7144b2/python/pyspark/pandas/tests/indexes/test_base.py#L2249