code: def run_step(self, rewriter):
          
          assert rewriter, ("FileRewriter instance required to run "
                            "FileInRewriterStep.")
          rewriter.files_in_to_out(in_path=self.path_in, out_path=self.path_out)
docs: Do the file in to out rewrite.
  
          Doesn't do anything more crazy than call files_in_to_out on the
          rewriter.
  
          Args:
              rewriter: pypyr.filesystem.FileRewriter instance.