pandas test error induced by the io.json
#### Code Sample, a copy-pastable example if possible

```python
python3 setup.py test

```
#### Problem description

table_schema (unittest.loader._FailedTest) ... ERROR
json (unittest.loader._FailedTest) ... ERROR
normalize (unittest.loader._FailedTest) ... ERROR

======================================================================
ERROR: table_schema (unittest.loader._FailedTest)
----------------------------------------------------------------------
AttributeError: module 'pandas.io.json' has no attribute 'table_schema'

======================================================================
ERROR: json (unittest.loader._FailedTest)
----------------------------------------------------------------------
AttributeError: module 'pandas.io.json' has no attribute 'json'

======================================================================
ERROR: normalize (unittest.loader._FailedTest)
----------------------------------------------------------------------
AttributeError: module 'pandas.io.json' has no attribute 'normalize'

----------------------------------------------------------------------
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#### Expected Output

#### Output of ``pd.show_versions()``

<details>

[paste the output of ``pd.show_versions()`` here below this line]

</details>
