* @since 31.0
     */
    public ImmutableTable<R, C, V> buildOrThrow() {
      int size = cells.size();
      switch (size) {
        case 0:
          return of();
        case 1:
          return new SingletonImmutableTable<>(Iterables.getOnlyElement(cells));
        default:
          return RegularImmutableTable.forCells(cells, rowComparator, columnComparator);
      }
    }
  }

  ImmutableTable() {}

We are going to call them "**operations**" too.

#### Define a *path operation decorator*

```Python hl_lines="6"
{!../../../docs_src/first_steps/tutorial001.py!}
```

The `@app.get("/")` tells **FastAPI** that the function right below is in charge of handling requests that go to:

* the path `/`
* using a <abbr title="an HTTP GET method"><code>get</code> operation</abbr>

!!! info "`@decorator` Info"

    The `--no-cache-dir` option tells `pip` to not save the downloaded packages locally, as that is only if `pip` was going to be run again to install the same packages, but that's not the case when working with containers.

    !!! note
        The `--no-cache-dir` is only related to `pip`, it has nothing to do with Docker or containers.

    The `--upgrade` option tells `pip` to upgrade the packages if they are already installed.

}

// ShardSize - returns actual shared size from erasure blockSize.
func (e ErasureInfo) ShardSize() int64 {
	return ceilFrac(e.BlockSize, int64(e.DataBlocks))
}

// IsValid - tells if erasure info fields are valid.
func (fi FileInfo) IsValid() bool {
	if fi.Deleted {
		// Delete marker has no data, no need to check
		// for erasure coding information
		return true
	}

Then create a file `traefik.toml` with:

```TOML hl_lines="3"
[entryPoints]
  [entryPoints.http]
    address = ":9999"

[providers]
  [providers.file]
    filename = "routes.toml"
```

This tells Traefik to listen on port 9999 and to use another file `routes.toml`.

!!! tip
    We are using port 9999 instead of the standard HTTP port 80 so that you don't have to run it with admin (`sudo`) privileges.

	Version int          `msg:"v"`
	Pools   []PoolStatus `msg:"pls"`

	// Value should not be saved when we have not loaded anything yet.
	dontSave bool `msg:"-"`
}

// A decommission resumable tells us if decommission is worth
// resuming upon restart of a cluster.
func (p *poolMeta) returnResumablePools() []PoolStatus {
	var newPools []PoolStatus
	for _, pool := range p.Pools {
		if pool.Decommission == nil {