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

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

And we can even declare [global dependencies](dependencies/global-dependencies.md){.internal-link target=_blank} that will be combined with the dependencies for each `APIRouter`:

```Python hl_lines="1  3  7" title="app/main.py"
{!../../docs_src/bigger_applications/app/main.py!}
```

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

 * <ul>
 * <li>Web crawling - crawls web sites and web content</li>
 * <li>File system crawling - crawls file systems and documents</li>
 * <li>Data store crawling - crawls databases and other data sources</li>
 * <li>Combined crawling - runs multiple crawling types simultaneously</li>
 * </ul>
 *
 * <p>Command line usage:
 * <pre>
 * java org.codelibs.fess.exec.Crawler [options...]

    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

    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

  //
  // class Entry {
  //    int hash;
  //    Entry next;
  //    K key;
  //    V value;
  // }
  //
  // The imaginary `hash` and `next` values are combined into a single `int` value in the `entries`
  // array. The top bits of this value are the remaining bits of the hash value that were not used

    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

    }
    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

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

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

		}
	}

	// 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, ","))