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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def find(self, board: Union[chess.Board, int], *, minimum_weight: int = 1, exclude_moves: Container[chess.Move] = ()) -> Entry: """ Finds the main entry for the given position or Zobrist hash. The main entry is the (first) entry with the highest weight. By default, entries with weight ``0`` are excluded. This is a common way to delete entries from an opening book without compacting it. Pass *minimum_weight* ``0`` to select all entries. :raises: :exc:`IndexError` if no entries are found. Use :func:`~chess.polyglot.MemoryMappedReader.get()` if you prefer to get ``None`` instead of an exception. """

        try:
            return max(self.find_all(board, minimum_weight=minimum_weight, exclude_moves=exclude_moves), key=lambda entry: entry.weight)
        except ValueError:
            raise IndexError()