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Version: 1.1

A simple command-line application


This is a simple Hydra application that prints your configuration. The my_app function is a place holder for your code. We will slowly evolve this example to showcase more Hydra features.

The examples in this tutorial are available here.
from omegaconf import DictConfig, OmegaConf
import hydra
def my_app(cfg: DictConfig) -> None:
if __name__ == "__main__":

In this example, Hydra creates an empty cfg object and pass it to the function annotated with @hydra.main.

You can add config values via the command line. The + indicates that the field is new.

$ python +db.driver=mysql +db.user=omry +db.password=secret
driver: mysql
user: omry
password: secret

We will learn more about the config_path in the following pages.

See Hydra's command line flags and Basic Override Syntax for more information about the command line.

Last updated on by Jasha10