Function update_entity 

pub fn update_entity<T, I, F, E>(
    addr: &HoloHash<Action>,
    callback: F,
) -> Result<Entity<T>, WasmError>
where
    ScopedZomeType<EntryDefIndex>: for<'a> TryFrom<&'a I, Error = WasmError>,
    Entry: TryFrom<I, Error = E, Error = E> + TryFrom<T>,
    WasmError: From<E>,
    T: TryFrom<Record, Error = WasmError> + Clone + EntryModel<I>,
    F: FnOnce(T, Record) -> Result<T, WasmError>,

Update an entity