---------------------------------------------------------------------------
MessageError                              Traceback (most recent call last)
<ipython-input-3-292f82be1b7a> in <module>()
      1 from google.colab import files
      2 
----> 3 uploaded = files.upload()
      4 
      5 for fn in uploaded.keys():

/usr/local/lib/python3.6/dist-packages/google/colab/files.py in upload()
     59   result = output.eval_js(
     60       'google.colab._files._uploadFiles("{input_id}", "{output_id}")'.format(
---> 61           input_id=input_id, output_id=output_id))
     62   files = collections.defaultdict(six.binary_type)
     63 

/usr/local/lib/python3.6/dist-packages/google/colab/output/_js.py in eval_js(script, ignore_result)
     37   if ignore_result:
     38     return
---> 39   return _message.read_reply_from_input(request_id)
     40 
     41 

/usr/local/lib/python3.6/dist-packages/google/colab/_message.py in read_reply_from_input(message_id, timeout_sec)
     84         reply.get('colab_msg_id') == message_id):
     85       if 'error' in reply:
---> 86         raise MessageError(reply['error'])
     87       return reply.get('data', None)
     88 

MessageError: TypeError: google.colab._files is undefined