companion PR for https://github.com/paritytech/substrate/pull/13373 (#2547)

* companion PR for https://github.com/paritytech/substrate/pull/13373



* Add missing trait function

* Fix template

Signed-off-by: Oliver Tale-Yazdi <[email protected]>

* Add missing weight functions

Signed-off-by: Oliver Tale-Yazdi <[email protected]>

* update lockfile for {"polkadot", "substrate"}

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Signed-off-by: Oliver Tale-Yazdi <[email protected]>
Co-authored-by: Falco Hirschenberger <[email protected]>
Co-authored-by: Oliver Tale-Yazdi <[email protected]>
Co-authored-by: parity-processbot <>