In [2]: import xorbits

In [3]: xorbits.init()
2023-09-26 15:55:08,918 xorbits._mars.deploy.oscar.local 86719 WARNING  Web service started at http://0.0.0.0:36934

In [4]: df = pd.DataFrame(columns=['a', 'b', 'c'])

In [5]: def p(d):
   ...:     if not len(d):
   ...:         return pd.DataFrame([[None] * d.shape[1]], columns=d.columns)
   ...:     else:
   ...:         return d
   ...: 

In [6]: df.map_chunk(p)  # should not be empty
100%|████████████████████████████████████| 100.00/100 [00:00<00:00, 2450.02it/s]

Empty DataFrame
Columns: [a, b, c]
Index: []