And then **FastAPI** will call that override instead of the original dependency.

{* ../../docs_src/dependency_testing/tutorial001_an_py310.py hl[26:27,30] *}

/// tip

You can set a dependency override for a dependency used anywhere in your **FastAPI** application.

///

## Dependencies errors and return values { #dependencies-errors-and-return-values }

You can use the same dependency *functions* you use normally.

### Dependency requirements { #dependency-requirements }

They can declare request requirements (like headers) or other sub-dependencies:

{* ../../docs_src/dependencies/tutorial006_an_py39.py hl[8,13] *}

  <artifactId>t06-b</artifactId>
  <packaging>jar</packaging>
  <version>1.0</version>
  <dependencies>
    <dependency>
      <groupId>maven-test</groupId>
      <artifactId>t06-c</artifactId>
      <version>1.0</version>
      <type>jar</type>
      <scope>compile</scope>
    </dependency>
    <dependency>
      <groupId>maven-test</groupId>
      <artifactId>t06-d</artifactId>
      <version>1.1</version>

                                "The requested dependency version range '%s' does not specify an upper bound",
                                dependency.getVersion()),
                        dependency.getGroupId(),
                        dependency.getArtifactId(),
                        dependency.getVersion());
            }

            dependency.setVersion(versionRangeResult.getHighestVersion().toString());

    <version>0.1-SNAPSHOT</version>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>test</groupId>
                <artifactId>mydep</artifactId>
                <version>0.2</version>
            </dependency>
            <dependency>
                <groupId>test</groupId>
                <artifactId>import</artifactId>

  <dependencyManagement>
    <dependencies>
      <dependency>
        <groupId>maven-test</groupId>
        <artifactId>t08-a</artifactId>
        <version>1.0</version>
      </dependency>
      <dependency>
        <groupId>maven-test</groupId>
        <artifactId>t08-b</artifactId>
        <version>1.1</version>
      </dependency>
      <dependency>
        <groupId>maven-test</groupId>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>test</groupId>
                <artifactId>other</artifactId>
                <version>0.1-SNAPSHOT</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>test</groupId>
                <artifactId>import</artifactId>

  <dependencyManagement>

    <dependencies>

      <dependency>
        <groupId>maven-test</groupId>
        <artifactId>t04-a</artifactId>
        <version>1.0</version>
      </dependency>

      <dependency>
        <groupId>maven-test</groupId>
        <artifactId>t04-b</artifactId>
        <version>1.0</version>
      </dependency>

    <dependency>
      <groupId>maven-test</groupId>

  <dependencies>
    <dependency>
      <groupId>com.google.guava</groupId>
      <artifactId>failureaccess</artifactId>
      <version>${failureaccess.version}</version>
    </dependency>
    <dependency>
      <groupId>com.google.guava</groupId>
      <artifactId>listenablefuture</artifactId>
      <version>${listenablefuture.version}</version>
    </dependency>
    <dependency>
      <groupId>org.jspecify</groupId>

  </scm>
  <dependencyManagement>
    <dependencies>
      <dependency>
        <groupId>maven-test</groupId>
        <artifactId>t05-b</artifactId>
        <version>1.0</version>
      </dependency>
      <dependency>
        <groupId>maven-test</groupId>
        <artifactId>t05-d</artifactId>
        <version>1.0</version>
      </dependency>
    </dependencies>
  </dependencyManagement>
  <dependencies>