Upload assets files to S3

def assets2s3():
    """ Upload assets files to S3 """
    import flask_s3

    header("Assets2S3...")
    print("")
    print("Building assets files..." )
    print("")
    build_assets(application.app)
    print("")
    print("Uploading assets files to S3 ...")
    flask_s3.create_all(application.app)
    print("")