title: Trying to read BSON file, get bson.errors.InvalidBSON: objsize too large
body: <p>I am currently trying to read a bson file to import it into a database. I can already read the file and print it as as bytes, but I end up just getting an <code>bson.errors.InvalidBSON: objsize too large</code> error.</p>
  
  <p>This is the code that is trying to decode the file</p>
  
  <pre><code>with zip.open(name) as myfile:
      content = myfile.read()
      print(content)
      print(bson.decode_all(content))
  </code></pre>
  
  <p>and this is the output i get</p>
  
  <pre><code>b'[{"_id": {"$oid": "5bf3cf511c9d44000088c376"}, "some": "sort of"}, {"_id": {"$oid": "5bf3cf5c1c9d44000088c377"}, "test": "data"}]'
  Traceback (most recent call last):
    File "/home/jonas/.envs/mongodb-backup-py-aGZYxULQ/bin/mongo-backup", line 11, in &lt;module&gt;
      load_entry_point('mongo-backup-cli', 'console_scripts', 'mongo-backup')()
    File "/home/jonas/.envs/mongodb-backup-py-aGZYxULQ/lib/python3.6/site-packages/click/core.py", line 764, in __call__
      return self.main(*args, **kwargs)
    File "/home/jonas/.envs/mongodb-backup-py-aGZYxULQ/lib/python3.6/site-packages/click/core.py", line 717, in main
      rv = self.invoke(ctx)
    File "/home/jonas/.envs/mongodb-backup-py-aGZYxULQ/lib/python3.6/site-packages/click/core.py", line 1137, in invoke
      return _process_result(sub_ctx.command.invoke(sub_ctx))
    File "/home/jonas/.envs/mongodb-backup-py-aGZYxULQ/lib/python3.6/site-packages/click/core.py", line 956, in invoke
      return ctx.invoke(self.callback, **ctx.params)
    File "/home/jonas/.envs/mongodb-backup-py-aGZYxULQ/lib/python3.6/site-packages/click/core.py", line 555, in invoke
      return callback(*args, **kwargs)
    File "/home/jonas/work/mongodb-backup-py/mongo_backup/cli.py", line 45, in restore
      restore_files(uri, db_name, file.name)
    File "/home/jonas/work/mongodb-backup-py/mongo_backup/restore.py", line 6, in restore_files
      print(read_zip_file(file))
    File "/home/jonas/work/mongodb-backup-py/mongo_backup/zip.py", line 24, in read_zip_file
      print(bson.decode_all(content))
  bson.errors.InvalidBSON: objsize too large
  </code></pre>