commons: Annotated[dict, Depends(common_parameters)]
```

But because we are using `Annotated`, we can store that `Annotated` value in a variable and use it in multiple places:

{* ../../docs_src/dependencies/tutorial001_02_an_py310.py hl[12,16,21] *}

/// tip

This is just standard Python, it's called a "type alias", it's actually not specific to **FastAPI**.

import org.jspecify.annotations.Nullable;

/**
 * An {@link Escaper} that converts literal text into a format safe for inclusion in a particular
 * context (such as an XML document). Typically (but not always), the inverse process of
 * "unescaping" the text is performed automatically by the relevant parser.
 *
 * <p>For example, an XML escaper would convert the literal string {@code "Foo<Bar>"} into {@code

import org.jspecify.annotations.Nullable;

/**
 * An {@link Escaper} that converts literal text into a format safe for inclusion in a particular
 * context (such as an XML document). Typically (but not always), the inverse process of
 * "unescaping" the text is performed automatically by the relevant parser.
 *
 * <p>For example, an XML escaper would convert the literal string {@code "Foo<Bar>"} into {@code

 * #delegate()} method must be overridden to return the instance being decorated.
 *
 * <p>This class does <i>not</i> forward the {@code hashCode} and {@code equals} methods through to
 * the backing object, but relies on {@code Object}'s implementation. This is necessary to preserve
 * the symmetry of {@code equals}. Custom definitions of equality are usually based on an interface,

**FastAPI** will make sure to read that data from the right place instead of JSON.

/// note | Technical Details

Data from forms is normally encoded using the "media type" `application/x-www-form-urlencoded`.

But when the form includes files, it is encoded as `multipart/form-data`. You'll read about handling files in the next chapter.

      }
      throw new AssertionError(
          "expected to throw " + expectedThrowable.getSimpleName() + " but threw " + t, t);
    }
    if (userPassedSupplier) {
      throw new AssertionError(
          "expected to throw "
              + expectedThrowable.getSimpleName()
              + " but returned result: "
              + result);
    } else {

      }
      throw new AssertionError(
          "expected to throw " + expectedThrowable.getSimpleName() + " but threw " + t, t);
    }
    if (userPassedSupplier) {
      throw new AssertionError(
          "expected to throw "
              + expectedThrowable.getSimpleName()
              + " but returned result: "
              + result);
    } else {

      }
      throw new AssertionError(
          "expected to throw " + expectedThrowable.getSimpleName() + " but threw " + t, t);
    }
    if (userPassedSupplier) {
      throw new AssertionError(
          "expected to throw "
              + expectedThrowable.getSimpleName()
              + " but returned result: "
              + result);
    } else {

      }
      throw new AssertionError(
          "expected to throw " + expectedThrowable.getSimpleName() + " but threw " + t, t);
    }
    if (userPassedSupplier) {
      throw new AssertionError(
          "expected to throw "
              + expectedThrowable.getSimpleName()
              + " but returned result: "
              + result);
    } else {

      }
      throw new AssertionError(
          "expected to throw " + expectedThrowable.getSimpleName() + " but threw " + t, t);
    }
    if (userPassedSupplier) {
      throw new AssertionError(
          "expected to throw "
              + expectedThrowable.getSimpleName()
              + " but returned result: "
              + result);
    } else {