simple regex question

[Dwight E Chadbourne]

Hi all.  I want the 20 digit hash in this text.

d5:filesd20:xxxxxxxxxxxxxxxxxxxxd8:completei2e10:downloadedi0e10:incompletei4e
4:name12:xxxxxxxxxxxxee5:flagsd20:min_request_intervali3600eee

How do I get only the xxxxxxxxxxxxxxxxxxxx and not the preceding 
identifier?

filesd20:.{20} returns the "filesd20:" but I don't need that.  Is there a 
way to do it only with regex?

Thanks for any tips or links.

- Eric C.




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