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Version: 1.1

A simple command-line application

Β Example (Click Here)

This is a simple Hydra application that prints your configuration. The my_app function is a placeholder 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 passes 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.