Extract non-contiguous, multiple ranges from an XLSX sheet?

[visnup]

The .sheet() function to extract data out of a XLSX sheet is limited to specifying a single, contiguous range. We've seen several cases so far where after extracting an initial range, we need to re-filter the result to skip empty rows that are interleaved with the data.

Currently we can do this in the notebook, but there might be a more flexible API to make this easier?

[visnup]

Another case: keep reading rows but stop short of a totals or summary row. Although in that case, supporting "negative" rows or columns similar to slice could work. For example, "2:-10".