code: @Nonnull
    public static ImmutableKeyValueSource<Symbol, ByteSource> fromPalDB(final File dbFile)
        throws IOException {
      return PalDBKeyValueSource.fromFile(dbFile);
    }
docs: Creates a new key-value source based on the contents of the specified embedded database.
  
  @param dbFile a database file created using {@link KeyValueSinks#forPalDB(File, boolean)}
  @return a key-value source
  @throws IOException if the database could not be opened for reading