### Import `FastAPI` { #import-fastapi }

You import and create a `FastAPI` class as normally.

And we can even declare [global dependencies](dependencies/global-dependencies.md) that will be combined with the dependencies for each `APIRouter`:

{* ../../docs_src/bigger_applications/app_an_py310/main.py hl[1,3,7] title["app/main.py"] *}

### Import the `APIRouter` { #import-the-apirouter }

        Callable<C> combiner, Executor executor) {
      return new CombinedFuture<>(futures, allMustSucceed, executor, combiner);
    }

    /**
     * Creates the {@link ListenableFuture} which will return the result of running {@code combiner}
     * when all Futures complete. {@code combiner} will run using {@code executor}.
     *

    checkState(
        this.maximumWeight == UNSET_INT,
        "maximum weight was already set to %s",
        this.maximumWeight);
    checkState(this.weigher == null, "maximum size can not be combined with weigher");
    checkArgument(maximumSize >= 0, "maximum size must not be negative");
    this.maximumSize = maximumSize;
    return this;
  }

  /**

	var wg sync.WaitGroup

	args := LockArgs{
		Owner:     owner,
		UID:       id,
		Resources: names,
		Source:    source,
		Quorum:    &quorum,
	}

	// Combined timeout for the lock attempt.
	ctx, cancel := context.WithTimeout(ctx, ds.Timeouts.Acquire)
	defer cancel()

	// Special context for NetLockers - do not use timeouts.

    checkArgument(min <= max, "min (%s) must be less than or equal to max (%s)", min, max);
    return value < min ? min : value < max ? value : max;
  }

  /**
   * Returns the values from each provided array combined into a single array. For example, {@code
   * concat(new char[] {a, b}, new char[] {}, new char[] {c}} returns the array {@code {a, b, c}}.
   *
   * @param arrays zero or more {@code char} arrays

    checkArgument(min <= max, "min (%s) must be less than or equal to max (%s)", min, max);
    return value < min ? min : value < max ? value : max;
  }

  /**
   * Returns the values from each provided array combined into a single array. For example, {@code
   * concat(new short[] {a, b}, new short[] {}, new short[] {c}} returns the array {@code {a, b,
   * c}}.
   *
   * @param arrays zero or more {@code short} arrays

    checkState(
        this.maximumWeight == UNSET_INT,
        "maximum weight was already set to %s",
        this.maximumWeight);
    checkState(this.weigher == null, "maximum size can not be combined with weigher");
    checkArgument(maximumSize >= 0, "maximum size must not be negative");
    this.maximumSize = maximumSize;
    return this;
  }

  /**

    }
    throw new IllegalArgumentException(
        lenientFormat("min (%s) must be less than or equal to max (%s)", min, max));
  }

  /**
   * Returns the values from each provided array combined into a single array. For example, {@code
   * concat(new float[] {a, b}, new float[] {}, new float[] {c}} returns the array {@code {a, b,
   * c}}.
   *
   * @param arrays zero or more {@code float} arrays

// Sync pending nodes in local executors (including the context default executor
// and thread executors) and streaming requests to remote executors, and get the
// combined status.
TF_CAPI_EXPORT extern void TFE_ContextAsyncWait(TFE_Context* ctx,
                                                TF_Status* status);

// This function will block till the operation that produces `h` has

		}
	}

	// Defensive code: Do not allow any operation if no policy is found in the session token
	if !isOwnerDerived && len(policies) == 0 {
		return false
	}

	// 2. Combine the mapped policies into a single combined policy.

	var combinedPolicy policy.Policy
	// Policies were found, evaluate all of them.
	if !isOwnerDerived {
		availablePoliciesStr, c := sys.store.MergePolicies(strings.Join(policies, ","))