code: def hashes_get(versions_file, base_path):
      
      files = versions_file.files_get_all()
      result = {}
      for f in files:
          try:
              result[f] = functions.md5_file(base_path + f)
          except IOError:
              # Not all files exist for all versions.
              pass
  
      return result
docs: Gets hashes for currently checked out version.
      @param versions_file: a common.VersionsFile instance to check against.
      @param base_path: where to look for files. e.g. './.update-workspace/silverstripe/'
      @return: checksums {'file1': 'hash1'}