[{'role': 'system', 'content': "You are an expert in machine learning and your task is to classify code snippets into one of the following categories: ['helper_functions', 'load_data', 'data_exploration', 'data_preprocessing', 'evaluation', 'modelling', 'prediction', 'result_visualization', 'save_results', 'comment_only']."}, {'role': 'user', 'content': 'Identify the single most appropriate category to which the provided code belongs. Provide your response as a single category label without any additional information, commentary, or personal opinions.\\nPython Code:def sentence_to_seq(sentence, vocab_to_int):\n"""\nConvert a sentence to a sequence of ids\n:param sentence: String\n:param vocab_to_int: Dictionary to go from the words to an id\n:return: List of word ids\n"""\nsentence = sentence.lower().split()\nword_ids = [vocab_to_int.get(word, vocab_to_int[\'<UNK>\']) for word in sentence]\nreturn word_ids\n"""\nDON\'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE\n"""\ntests.test_sentence_to_seq(sentence_to_seq)'}, {'role': 'assistant', 'content': 'data_preprocessing'}]