You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: find_return_value.rb
    path of file: ./repos/brakeman/lib/brakeman/processors/lib
    
    the code of the file until where you have to start completion: require 'brakeman/processors/alias_processor'

#Attempts to determine the return value of a method.
#
#Prefe
    
  def last_value exp
    case exp.node_type
    when :rlist, :block, :scope, Sexp
      last_value exp.last
    when :if
      then_clause = exp.then_clause
      else_clause = exp.else_clause

      if then_clause.nil? and else_clause.nil?
        nil
      elsif then_clause.nil?
        last_value else_clause
      elsif else_clause.nil?
        last_value then_clause
      else
        true_branch = last_value then_clause
        false_branch = last_value else_clause

        if true_branch and false_branch
          value = make_or(true_branch, false_branch)
          value.original_line = value.rhs.line
          value
        else #Unlikely?
          true_branch or false_branch
        end