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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 fmt_sentence(text):
 """English sentence formatter. First letter is always upper case. Example: "Do you want to build a snow man?" **中文文档** 句子格式。每句话的第一个单词第一个字母大写。 """

    text = text.strip()
    if len(text) == 0:  # if empty string, return it
        return text
    else:
        text = text.lower()  # lower all char
        # delete redundant empty space
        chunks = [chunk for chunk in text.split(" ") if len(chunk) >= 1]
        chunks[0] = chunks[0][0].upper() + chunks[0][1:]
        return " ".join(chunks)