python 2.7 unicode编写器健壮到NoneType

Question

我希望使用官方示例中的UnicodeWriter在尝试进行CSV写入时不会在Unicode数据上出现问题。然而，如果我在列表中有空白/缺失/NaN，应该是一行，我得到这个错误:

    self.writer.writerow([s.encode("utf-8") for s in row])
AttributeError: 'NoneType' object has no attribute 'encode'

有简单的修复方法吗?

我重复下面的"官方代码":

class UnicodeWriter:
    """
    A CSV writer which will write rows to CSV file "f",
    which is encoded in the given encoding.
    """
    def __init__(self, f, dialect=csv.excel, encoding="utf-8", **kwds):
        # Redirect output to a queue
        self.queue = cStringIO.StringIO()
        self.writer = csv.writer(self.queue, dialect=dialect, **kwds)
        self.stream = f
        self.encoder = codecs.getincrementalencoder(encoding)()
    def writerow(self, row):
        self.writer.writerow([s.encode("utf-8") for s in row])
        # Fetch UTF-8 output from the queue ...
        data = self.queue.getvalue()
        data = data.decode("utf-8")
        # ... and reencode it into the target encoding
        data = self.encoder.encode(data)
        # write to the target stream
        self.stream.write(data)
        # empty queue
        self.queue.truncate(0)
    def writerows(self, rows):
        for row in rows:
            self.writerow(row)

Answer 1

前面的问题(虽然是关于数字的字符串转换)也解决了这个问题，参见这个答案。只需添加一个unicode转换:self.writer.writerow([unicode(s).encode("utf-8") for s in row])