code: public CommandLine setOut(PrintWriter out) {
          this.out = Assert.notNull(out, "out");
          for (CommandLine sub : getSubcommands().values()) { sub.setOut(out); }
          return this;
      }
docs: Sets the writer to use when printing user-requested usage help or version help during command {@linkplain #execute(String...) execution}.
  <p>This method is used by {@link #execute(String...)}. Custom {@code IExecutionStrategy} implementations should also use this writer.</p>
  @param out the new PrintWriter to use
  @return this CommandLine for method chaining
  @since 4.0