[Python] pyarrow.array returns NullArray for array of unsupported Python objects

[asfimport]

In [4]: arr = np.array([datetime.timedelta(1), datetime.timedelta(2)])

In [5]: pa.array(arr)
Out[5]: 
<pyarrow.lib.NullArray object at 0x7fbb612bba48>
[
  NA,
  NA
]

Reporter: Wes McKinney / @wesm
Assignee: Wes McKinney / @wesm

_{Note: This issue was originally created as ARROW-1222. Please see the migration documentation for further details.}

[asfimport]

Wes McKinney / @wesm:
PR: #854

[asfimport]

Wes McKinney / @wesm:
Issue resolved by pull request 854
#854