How upload file authenticated in s3 bucket with python

i usualy used my aplication for upload files in s3 bucket, but accessing aws console, when click in open, the file dont open but do downloaded. why this happened? i am used this code below to upload.

  s3_client = boto3.client('s3', aws_access_key_id=AWS_ACCESS_KEY_ID, aws_secret_access_key=AWS_SECRET_ACCESS_KEY)
            s3_client.upload_file(file, S3_BUCKET, item_drop_down + '/{}'.format(arquivo.filename))