def upload_s3(dirpath: str) -> None:
    import boto3, time

    real_filepath = ''
    compressed_filepath = compress_backup(dirpath)

    if c.S3_GPG_ENCRYPT and not c.NOGPG:
        real_filepath = gpg_encrypt_file(compressed_filepath)

    real_filepath = compressed_filepath if not real_filepath else real_filepath
    datepart = time.strftime("%Y%m%d%H%M%S")
    remote_filename = os.path.split(real_filepath)[1] + '.' + datepart

    with open(real_filepath, 'rb') as data:
        message('Uploading file to Amazon S3')

        if not c.DRY_RUN:
            s3 = boto3.client('s3', aws_access_key_id=c.S3_ACCESS_KEY,
                    aws_secret_access_key=c.S3_SECRET_KEY)
            s3.upload_fileobj(data, c.S3_BUCKET, remote_filename)

    if not c.DRY_RUN:
        if c.S3_GPG_ENCRYPT:
            # Remove the local encrupted file
            os.unlink(real_filepath)
        os.unlink(compressed_filepath)

    message('File uploaded to S3 bucket "{}" as key "{}"'.
            format(c.S3_BUCKET, remote_filename))