How to use the @reactivex/ix-es2015-cjs/asynciterable/pipe/flatmap.flatMap function in @reactivex/ix-es2015-cjs

public iterBlocks(options: IterOptions = {}): AsyncIterable {
    return AsyncIterableX.from(this.getProvider()).pipe(flatMap((provider) => provider.iterBlocks(options)));
  }

public iterActionsRaw(options: IterOptions = {}): AsyncIterable {
    return AsyncIterableX.from(this.iterBlocks(options)).pipe(
      flatMap(async (block) => {
        const actions = _.flatten(
          block.transactions.map((transaction) => {
            if (transaction.type === 'InvocationTransaction') {
              return [...transaction.invocationData.actions];
            }

            return [];
          }),
        );

        return AsyncIterableX.of(...actions);
      }),
    );
  }

public iterActionsRaw(options: IterOptions = {}): AsyncIterable {
    return AsyncIterableX.from(this.getProvider()).pipe(
      flatMap((provider) => provider.iterActionsRaw(options)),
    );
  }