code: def rename(self, new_path, force=False):
          
          new_path = self.to_full_path(new_path)
          if self.path == new_path:
              return self
  
          new_abs_path = osp.join(_git_dir(self.repo, new_path), new_path)
          cur_abs_path = osp.join(_git_dir(self.repo, self.path), self.path)
          if osp.isfile(new_abs_path):
              if not force:
                  # if they point to the same file, its not an error
                  with open(new_abs_path, 'rb') as fd1:
                      f1 = fd1.read().strip()
                  with open(cur_abs_path, 'rb') as fd2:
                      f2 = fd2.read().strip()
                  if f1 != f2:
                      raise OSError("File at path %r already exists" % new_abs_path)
                  # else: we could remove ourselves and use the otherone, but
                  # but clarity we just continue as usual
              # END not force handling
              os.remove(new_abs_path)
          # END handle existing target file
  
          dname = osp.dirname(new_abs_path)
          if not osp.isdir(dname):
              os.makedirs(dname)
          # END create directory
  
          os.rename(cur_abs_path, new_abs_path)
          self.path = new_path
  
          return self
docs: Rename self to a new path
  
          :param new_path:
              Either a simple name or a full path, i.e. new_name or features/new_name.
              The prefix refs/ is implied for references and will be set as needed.
              In case this is a symbolic ref, there is no implied prefix
  
          :param force:
              If True, the rename will succeed even if a head with the target name
              already exists. It will be overwritten in that case
  
          :return: self
          :raise OSError: In case a file at path but a different contents already exists