为什么我的代码不写入文件输出？赋值前引用的局部变量

Question

我写了一些代码，通过阅读我的文本文件，找到一组与基因相关的数字，然后用这些数字搜索基因本身，这样我就可以提取一堆包含每个基因的文本文件。我已经成功地得到了数字，但我有问题的文件写作。得到错误“local variable”gene_substring“referenced before assignation”。我做了一些研究，并尝试使用global来修复它，但它在其他地方抛出了错误。

#function to extract the genes by using the numbers in my list
end_file = "/Users...."

def extract_genes(start_stop, genome_sequence):
    for start,stop in start_stop:
        # extracts start:stop gene from the sequence
            if start > stop:
                gene_substring = genome_sequence[0:start] + genome_sequence[stop:]

            # store in file
            with open(end_file + "/" + name + "+" + ".txt", "w",) as file:
                file.write(gene_substring)

#My code to get the output

work_dir = "/Users/"
for path in glob.glob(os.path.join(work_dir, "*.gbff")):
    numbers = extract_numbers(path)
    sequences = extract_seq(path)
    extract_genes(start_stop, sequences)
    print(path)

我该怎么解决这个？谢谢：）

Answer 1

变量gene_substring仅在条件start>stop为true时初始化。但如果没有达到要求怎么办？您必须初始化变量gene_substring，或者简单地移动它

with open(end_file + "/" + name + "+" + ".txt", "w",) as file:
                file.write(gene_substring)

进入语句if start>stop:

此外，请确保if语句正确