Convert Jira's time tracking field format to hours

I am using JIRA api to extract timespent by users on issues. The time spent is in the format:

"12w 1d 2h 5m" or "12h" or "12m" etc

The API isn't exporting the number of hours. Is there a quick (requires no effort on my part) way to convert this to hours (or seconds). I suppose this is some sort of a standard format, is there a name for it? I know how to do this myself, just don't want to reinvent the wheel

via Chebli Mohamed