问无法安装therubyracer，错误

EN

Installing therubyracer-heroku (0.8.1.pre3) with native extensions C:/RailsInsta
ller/Ruby1.9.2/lib/ruby/site_ruby/1.9.1/rubygems/installer.rb:533:in `rescue in
block in build_extensions': ERROR: Failed to build gem native extension. (Gem::I
nstaller::ExtensionBuildError)

        C:/RailsInstaller/Ruby1.9.2/bin/ruby.exe extconf.rb
rm -rf build
mkdir -p build
cp -r scons build
mkdir -p build/scons/install
python build/scons/setup.py install --prefix=install
make: python: Command not found
make: *** [build/scons/install/bin/scons] Error 127
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

Provided configuration options:
        --with-opt-dir
        --without-opt-dir
        --with-opt-include
        --without-opt-include=${opt-dir}/include
        --with-opt-lib
        --without-opt-lib=${opt-dir}/lib
        --with-make-prog
        --without-make-prog
        --srcdir=.
        --curdir
        --ruby=C:/RailsInstaller/Ruby1.9.2/bin/ruby
extconf.rb:9:in `<main>': Error compiling V8 (RuntimeError)
Compiling V8


Gem files will remain installed in C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9
.1/gems/therubyracer-heroku-0.8.1.pre3 for inspection.
Results logged to C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/therubyra
cer-heroku-0.8.1.pre3/ext/v8/gem_make.out
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/site_ruby/1.9.1/rubygems/insta
ller.rb:511:in `block in build_extensions'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/site_ruby/1.9.1/rubygems/insta
ller.rb:486:in `each'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/site_ruby/1.9.1/rubygems/insta
ller.rb:486:in `build_extensions'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/site_ruby/1.9.1/rubygems/insta
ller.rb:159:in `install'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/lib/bundler/source.rb:101:in `block in install'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/lib/bundler/rubygems_integration.rb:78:in `preserve_paths'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/lib/bundler/source.rb:91:in `install'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/lib/bundler/installer.rb:58:in `block (2 levels) in run'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/lib/bundler/rubygems_integration.rb:93:in `with_build_args'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/lib/bundler/installer.rb:57:in `block in run'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/lib/bundler/installer.rb:49:in `run'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/lib/bundler/installer.rb:8:in `install'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/lib/bundler/cli.rb:220:in `install'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/lib/bundler/vendor/thor/task.rb:22:in `run'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/lib/bundler/vendor/thor/invocation.rb:118:in `invoke_task'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/lib/bundler/vendor/thor.rb:263:in `dispatch'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/lib/bundler/vendor/thor/base.rb:386:in `start'
        from C:/RailsInstaller/Ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.18
/bin/bundle:13:in `<top (required)>'
        from C:/RailsInstaller/Ruby1.9.2/bin/bundle:19:in `load'
        from C:/RailsInstaller/Ruby1.9.2/bin/bundle:19:in `<main>'