以下代码有何处错误，指出并修改。input_texts = [] target_texts = [] input_characters = set() target_characters = set() with open(data_path, 'r', encoding='utf-8') as f: lines = f.read().split('\n') for line in lines[: min(num_samples, len(lines) - 1)]: input_text,target_text = line.split('\t') target_text = '\t' + target_text + '\n' input_texts.append(input_text) target_texts.append(target_text) for char in input_text: if char not in input_characters: input_characters.add(char) for char in target_text: if char not in target_characters: target_characters.add(char) input_characters = sorted(list(input_characters)) target_characters = sorted(list(target_characters))

在代码中，第6行的`input_text,target_text = line.split('\t')`语句有可能会抛出异常，因为在读取数据时，有可能有些行并没有以`\t`作为分隔符。如果出现这样的情况，这一行代码就会导致程序出错。为了避免这种情况，可以加上异常处理机制，比如使用try-except语句。此外，在第9行和第12行中，`for char in input_text:`和`for char in target_text:`语句应该修改为`for char in input_text.strip():`和`for char in target_text.strip():`，以避免在字符集中添加空格符或换行符。修改后的代码如下：

input_texts = []
target_texts = []
input_characters = set()
target_characters = set()

with open(data_path, 'r', encoding='utf-8') as f:
    lines = f.read().split('\n')
    for line in lines[: min(num_samples, len(lines) - 1)]:
        try:
            input_text,target_text = line.split('\t')
            target_text = '\t' + target_text + '\n'
            input_texts.append(input_text)
            target_texts.append(target_text)
            for char in input_text.strip():
                if char not in input_characters:
                    input_characters.add(char)
            for char in target_text.strip():
                if char not in target_characters:
                    target_characters.add(char)
        except ValueError:
            pass

input_characters = sorted(list(input_characters))
target_characters = sorted(list(target_characters))