Loads and preprocessed data for the MR dataset.
    Returns input vectors, labels, vocabulary, and inverse vocabulary.

def load_data():
    """Loads and preprocessed data for the MR dataset.
    Returns input vectors, labels, vocabulary, and inverse vocabulary.
    """
    # Load and preprocess data
    sentences, labels = load_data_and_labels()
    sentences_padded = pad_sentences(sentences)
    vocabulary, vocabulary_inv = build_vocab(sentences_padded)
    x, y = build_input_data(sentences_padded, labels, vocabulary)
    return [x, y, vocabulary, vocabulary_inv]