new_contents: import sh
  
  
  class Repo(object):
      def __init__(self, local):
          self.git = sh.git.bake(_cwd=local)
  
      def checkout(self, head):
          self.git.checkout(head)
  
      def clone(self, remote):
          return self.git.clone(remote)
  
      def fetch(self, remote):
          return self.git.fetch(remote)
  
subject: add git wrapper