- github.com/posener/complete: [v1.1.1](https://github.com/posener/complete/tree/v1.1.1)
- github.com/ryanuber/columnize: [9b3edd6](https://github.com/ryanuber/columnize/tree/9b3edd6)
- github.com/sean-/seed: [e2103e2](https://github.com/sean-/seed/tree/e2103e2)
- github.com/subosito/gotenv: [v1.2.0](https://github.com/subosito/gotenv/tree/v1.2.0)
- github.com/willf/bitset: [d5bec33](https://github.com/willf/bitset/tree/d5bec33)

pkg go/doc, type Package struct, Examples []*Example
pkg go/doc, type Type struct, Examples []*Example
pkg hash/maphash, func MakeSeed() Seed
pkg hash/maphash, method (*Hash) BlockSize() int
pkg hash/maphash, method (*Hash) Reset()
pkg hash/maphash, method (*Hash) Seed() Seed
pkg hash/maphash, method (*Hash) SetSeed(Seed)
pkg hash/maphash, method (*Hash) Size() int
pkg hash/maphash, method (*Hash) Sum([]uint8) []uint8

- github.com/prometheus/tsdb: [v0.7.1](https://github.com/prometheus/tsdb/tree/v0.7.1)
- github.com/ryanuber/columnize: [9b3edd6](https://github.com/ryanuber/columnize/tree/9b3edd6)
- github.com/sean-/seed: [e2103e2](https://github.com/sean-/seed/tree/e2103e2)
- github.com/shurcooL/sanitized_anchor_name: [v1.0.0](https://github.com/shurcooL/sanitized_anchor_name/tree/v1.0.0)

// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"bytes"
	"context"
	"crypto/md5"
	"crypto/sha1"

- github.com/posener/complete: [v1.1.1](https://github.com/posener/complete/tree/v1.1.1)
- github.com/ryanuber/columnize: [9b3edd6](https://github.com/ryanuber/columnize/tree/9b3edd6)
- github.com/sean-/seed: [e2103e2](https://github.com/sean-/seed/tree/e2103e2)
- github.com/shurcooL/sanitized_anchor_name: [v1.0.0](https://github.com/shurcooL/sanitized_anchor_name/tree/v1.0.0)
- github.com/spf13/cast: [v1.3.1](https://github.com/spf13/cast/tree/v1.3.1)

Just use any kind of model, any kind of class, any kind of database that you need for your application. **FastAPI** has you covered with the dependency injection system.

## Code size { #code-size }

This example might seem verbose. Keep in mind that we are mixing security, data models, utility functions and *path operations* in the same file.

But here's the key point.

- github.com/posener/complete: [v1.1.1](https://github.com/posener/complete/tree/v1.1.1)
- github.com/ryanuber/columnize: [9b3edd6](https://github.com/ryanuber/columnize/tree/9b3edd6)
- github.com/sean-/seed: [e2103e2](https://github.com/sean-/seed/tree/e2103e2)
- github.com/smartystreets/assertions: [b2de0cb](https://github.com/smartystreets/assertions/tree/b2de0cb)

- github.com/posener/complete: [v1.1.1](https://github.com/posener/complete/tree/v1.1.1)
- github.com/ryanuber/columnize: [9b3edd6](https://github.com/ryanuber/columnize/tree/9b3edd6)
- github.com/sean-/seed: [e2103e2](https://github.com/sean-/seed/tree/e2103e2)
- github.com/smartystreets/assertions: [b2de0cb](https://github.com/smartystreets/assertions/tree/b2de0cb)

Adding an `\f` (an escaped "form feed" character) causes **FastAPI** to truncate the output used for OpenAPI at this point.

It won't show up in the documentation, but other tools (such as Sphinx) will be able to use the rest.

{* ../../docs_src/path_operation_advanced_configuration/tutorial004_py310.py hl[17:27] *}

## Additional Responses { #additional-responses }

# Advanced Dependencies { #advanced-dependencies }

## Parameterized dependencies { #parameterized-dependencies }

All the dependencies we have seen are a fixed function or class.

But there could be cases where you want to be able to set parameters on the dependency, without having to declare many different functions or classes.

Let's imagine that we want to have a dependency that checks if the query parameter `q` contains some fixed content.