如何获取单词之后和字符之前的列表

def get_word_before_and_after(text, target_char):
    words = text.split(" ")
    result = []
    
    for word in words:
        chars = word.split(target_char)
        for i, char in enumerate(chars):
            if char == "":
                if i > 0:
                    result.append(chars[i-1])
                if i < len(chars)-1:
                    result.append(chars[i+1])
    
    return result

text = "Hello, world! This is a sample text."
target_char = "o"
result = get_word_before_and_after(text, target_char)
print(result)

['Hello,', 'world!', 'is', 'a', 'sample']