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In some cases you don't really need the return value of a dependency inside your path operation function.
Or the dependency doesn't return a value.
But you still need it to be executed/solved.
For those cases, instead of declaring a path operation function parameter with Depends, you can add a list of dependencies to the path operation decorator.
Add dependencies to the path operation decorator
The path operation decorator receives an optional argument dependencies.
It should be a list of Depends():
{!./src/dependencies/tutorial006.py!}
These dependencies will be executed/solved the same way normal dependencies. But their value (if they return any) won't be passed to your path operation function.
!!! tip Some editors check for unused function parameters, and show them as errors.
Using these `dependencies` in the *path operation decorator* you can make sure they are executed while avoiding editor/tooling errors.
It might also help avoiding confusion for new developers that see an un-used parameter in your code and could think it's unnecessary.
Dependencies errors and return values
You can use the same dependency functions you use normally.
Dependency requirements
They can declare request requirements (like headers) or other sub-dependencies:
{!./src/dependencies/tutorial006.py!}
Raise exceptions
These dependencies can raise exceptions, the same as normal dependencies:
{!./src/dependencies/tutorial006.py!}
Return values
And they can return values or not, the values won't be used.
So, you can re-use a normal dependency (that returns a value) you already use somewhere else, and even though the value won't be used, the dependency will be executed:
{!./src/dependencies/tutorial006.py!}
Dependencies for a group of path operations
Later, when reading about how to structure bigger applications, possibly with multiple files, you will learn how to declare a single dependencies parameter for a group of path operations.