title: Having issue with bigquery API in python "AttributeError: 'NoneType' object has no attribute 'path'"
body: <p>I am trying to access bigquery using python and running into the following error and was wondering if you can help me out to debug the issue</p>
  
  <pre><code>delete_job = client.query(sql_raw)
      try:
          delete_job.result()  # Waits for job to complete.
          print("Job was successful")
      except exceptions.BadRequest:
          handle_exceptions(delete_job)
  
  Sql_raw = """delete from A.table_1 where activity_date in (select distinct  activity_date from A.table_B);
  
  insert into  A.table_1 select * from A.table_2 ;"""
  
  
  Error 
  
  Traceback (most recent call last):
    File "/Python_Envs/3.6.1/lib/python3.6/runpy.py", line 193, in _run_module_as_main
      "__main__", mod_spec)
    File "/Python_Envs/3.6.1/lib/python3.6/runpy.py", line 85, in _run_code
      exec(code, run_globals)
    File "/Python_Packages/ec2-python_old.zip/m/executor/__main__.py", line 192, in &lt;module&gt;
    File "/Python_Packages/ec2-python_old.zip/m/executor/__main__.py", line 183, in main
    File "/Python_Packages/ec2-python_old.zip/m/d/A/custom.py", line 223, in load
    File "/Python_Envs/3.6.1/lib/python3.6/site-packages/google/cloud/bigquery/job.py", line 1950, in result
      retry=retry)
    File "/Python_Envs/3.6.1/lib/python3.6/site-packages/google/cloud/bigquery/client.py", line 1274, in list_rows
      path='%s/data' % (table.path,),
  AttributeError: 'NoneType' object has no attribute 'path'
  
  </code></pre>
  
  <p>Update : I think its a bug with python 3.6.1 packages or something. I update my python to 3.6.5 and its working fine now.</p>