API: unpickle problems with pd.NaT #4606
Description
Error when reading a pickled pd.NaT value.
Example
In [1]: import pandas as pd In [2]: test_val = pd.NaT In [3]: from cPickle import loads, dumps In [4]: loads(dumps(test_val))--------------------------------------------------------------------------- TypeError Traceback (most recent call last) <ipython-input-12-8e4233b9b57a> in <module>() ----> 1 loads(dumps(pd.NaT)) TypeError: ('__new__() takes exactly one argument (2 given)', <class 'pandas.tslib.NaTType'>, ('\x00\x01\xff\xff\x00\x00\x00\x00\x00\x00',)) For the more common usage case
loads(dumps(pd.to_datetime(['2013-01-01', pd.NaT, '2014-01-06'])))
works as expected.