# File lib/puppet/relationship.rb, line 20
20:   def self.from_pson(pson)
21:     source = pson["source"]
22:     target = pson["target"]
23: 
24:     args = {}
25:     if event = pson["event"]
26:       args[:event] = event
27:     end
28:     if callback = pson["callback"]
29:       args[:callback] = callback
30:     end
31: 
32:     new(source, target, args)
33:   end