code: func getPolicy(segment string, tree *radix.Tree) (policy interface{}, found bool) {
  	found = false
  
  	tree.WalkPath(segment, func(path string, leaf interface{}) bool {
  		policies := leaf.(*policyAuthorizerRadixLeaf)
  		if policies.exact != nil && path == segment {
  			found = true
  			policy = policies.exact
  			return true
  		}
  
  		if policies.prefix != nil {
  			found = true
  			policy = policies.prefix
  		}
  		return false
  	})
  	return
  }
docs: // getPolicy first attempts to get an exact match for the segment from the "exact" tree and then falls
  // back to getting the policy for the longest prefix from the "prefix" tree