///

### Étape 2 : créer une "instance" `FastAPI`

{* ../../docs_src/first_steps/tutorial001.py hl[3] *}

Ici la variable `app` sera une "instance" de la classe `FastAPI`.

Ce sera le point principal d'interaction pour créer toute votre API.

Cette `app` est la même que celle à laquelle fait référence `uvicorn` dans la commande :

<div class="termy">

```console
$ uvicorn main:app --reload

/// check

So, with the same Python type declaration, **FastAPI** gives you data validation.

Notice that the error also clearly states exactly the point where the validation didn't pass.

This is incredibly helpful while developing and debugging code that interacts with your API.

///

## Documentation { #documentation }

      @Override
      public int resultIndex(int higherIndex) {
        return higherIndex;
      }
    },
    /**
     * Return {@code ~insertionIndex}, where {@code insertionIndex} is defined as the point at which
     * the key would be inserted into the list: the index of the next higher element in the list, or
     * {@code list.size()} if there is no such element.
     *

* Why is this change done? What's the use case?
* For user-facing features, what will the API look like?
* What test cases should it have? What could go wrong?
* How will it roughly be implemented? We'll happily provide code pointers to save you time.

We may ask you to answer these questions directly in the GitHub issue or (for large changes) in a shared Google Doc.

   * (though it still may be evicted by other means).
   *
   * <p><b>Important note:</b> Instead of returning this as a {@code CacheBuilder}
   * instance, this method returns {@code CacheBuilder<K1, V1>}. From this point on, either the
   * original reference or the returned reference may be used to complete configuration and build
   * the cache, but only the "generic" one is type-safe. That is, it will properly prevent you from

            assertEquals(0, size % 8, "Size should be aligned to 8-byte boundary");
        }

        @ParameterizedTest
        @DisplayName("Should calculate size for various lock counts")
        @ValueSource(ints = { 0, 1, 2, 5, 10, 20, 50, 100 })
        void testSizeWithVariousLockCounts(int lockCount) {
            Smb2Lock[] locks = new Smb2Lock[lockCount];
            for (int i = 0; i < lockCount; i++) {

        if (logger.isDebugEnabled()) {
            logger.debug("Detected delimiter: '{}' (count: {})", bestDelimiter, maxCount);
        }

        return bestDelimiter;
    }

    /**
     * Counts occurrences of a character in a string, excluding quoted sections.
     *
     * @param line the line to analyze
     * @param ch the character to count
     * @return the number of occurrences
     */

        verify(transport, times(3)).isSMB2();
    }

    // Inflight requests count including edge values
    @ParameterizedTest
    @DisplayName("getInflightRequests returns various counts")
    @ValueSource(ints = { 0, 1, 42, 1000 })
    void getInflightRequests_counts(int count) {
        when(transport.getInflightRequests()).thenReturn(count);
        assertEquals(count, transport.getInflightRequests());

///

## Sub Applications { #sub-applications }

    }

    @GwtIncompatible @J2ktIncompatible private static final long serialVersionUID = 0;
  }

  /**
   * Parses the specified string as a single-precision floating point value. The ASCII character
   * {@code '-'} (<code>'&#92;u002D'</code>) is recognized as the minus sign.
   *
   * <p>Unlike {@link Float#parseFloat(String)}, this method returns {@code null} instead of