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# CLI Arguments with Default
We can also use the same `typer.Argument()` to set a default value.
That way the *CLI argument* will be optional *and also* have a default value.
## An optional *CLI argument* with a default
We can also use `typer.Argument()` to make a *CLI argument* have a default value other than `None`:
{* docs_src/arguments/default/tutorial001_an.py hl[5] *}
/// tip
Because now the value will be a `str` passed by the user or the default value of `"Wade Wilson"` which is also a `str`, we know the value will never be `None`, so we don't have to (and shouldn't) use `Optional[str]`.
Have in mind that the `Optional[something]` tells Python that a value "could be `None`". But the use of `Optional` doesn't affect Typer in any way, e.g. it doesn't tell Typer if a value is required or not.
///
Check it:
<div class="termy">
```console
// Check the help
$ python main.py --help
// Notice the [default: Wade Wilson] ✨
Usage: main.py [OPTIONS] [NAME]
Arguments:
[NAME] [default: Wade Wilson]
Options:
--help Show this message and exit.
// With no optional CLI argument
$ python main.py
Hello Wade Wilson
// With one CLI argument
$ python main.py Camila
Hello Camila
```
</div>
## Dynamic default value
And we can even make the default value be dynamically generated by passing a function as the `default_factory` argument:
{* docs_src/arguments/default/tutorial002_an.py hl[7:8,11] *}
In this case, we created the function `get_name` that will just return a random `str` each time.
And we pass it as the first function argument to `typer.Argument()`.
/// tip
The word "factory" in `default_factory` is just a fancy way of saying "function that will create the default value".
///
Check it:
<div class="termy">
```console
// Check the help
$ python main.py --help
Usage: main.py [OPTIONS] [NAME]
Arguments:
[NAME] [default: (dynamic)]
Options:
--help Show this message and exit.
// Try it several times, it will use a random default each time
$ python main.py
Hello Deadpool
$ python main.py
Hello Hiro
$ python main.py
Hello Rick
// Now pass a value for the CLI argument
$ python main.py Camila
Hello Camila
```
</div>
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