code: def docs(session):
      
  
      # Build docs against the latest version of Python, because we can.
      session.interpreter = 'python3.6'
  
      # Set the virtualenv dirname.
      session.virtualenv_dirname = 'docs'
  
      # Install Sphinx and also all of the google-cloud-* packages.
      session.chdir(os.path.realpath(os.path.dirname(__file__)))
      session.install('-r', os.path.join('docs', 'requirements.txt'))
  
      # Build the docs!
      session.run(
          'bash', os.path.join('.', 'scripts', 'update_docs.sh'))
docs: Build the docs.