code: def rpm_compare(self, a, b):
          
          if a['version'] == b['version'] and \
             a['release'] == b['release'] and \
             a['signature'] == b['signature']:
              return
  
          raise ValueError("%s != %s" % (a, b))
docs: Compare rpm component version 'a' with 'b'.
          'name' is implied equal as it is the key() lookup