read_file.py

def read_file(file_id):
  """ 
  Download file from Google Drive 
  Argument: file_id
  Returns: downloaded file
  """
  
  file_id = file_id

  import io
  from googleapiclient.http import MediaIoBaseDownload

  request = drive_service.files().get_media(fileId=file_id)
  downloaded = io.BytesIO()
  downloader = MediaIoBaseDownload(downloaded, request)
  done = False
  while done is False:
    # _ is a placeholder for a progress object that we ignore.
    # (Our file is small, so we skip reporting progress.)
    _, done = downloader.next_chunk()

  downloaded.seek(0)
  return downloaded
  #print 'Downloaded file contents are:', downloaded.read()