General Unicode/UTF-8 support for csv files in Python 2.6

The example code of how to read Unicode given at http://docs.python.org/library/csv.html#examples looks to be obsolete, as it doesn’t work with Python 2.6 and 2.7.

Here follows UnicodeDictReader which works with utf-8 and may be with other encodings, but I only tested it on utf-8 inputs.

The idea in short is to decode Unicode only after a csv row has been split into fields by csv.reader.

class UnicodeCsvReader(object):
    def __init__(self, f, encoding="utf-8", **kwargs):
        self.csv_reader = csv.reader(f, **kwargs)
        self.encoding = encoding

    def __iter__(self):
        return self

    def next(self):
        # read and split the csv row into fields
        row = self.csv_reader.next() 
        # now decode
        return [unicode(cell, self.encoding) for cell in row]

    @property
    def line_num(self):
        return self.csv_reader.line_num

class UnicodeDictReader(csv.DictReader):
    def __init__(self, f, encoding="utf-8", fieldnames=None, **kwds):
        csv.DictReader.__init__(self, f, fieldnames=fieldnames, **kwds)
        self.reader = UnicodeCsvReader(f, encoding=encoding, **kwds)

Usage (source file encoding is utf-8):

csv_lines = (
    "абв,123",
    "где,456",
)

for row in UnicodeCsvReader(csv_lines):
    for col in row:
        print(type(col), col)

Output:

$ python test.py
<type 'unicode'> абв
<type 'unicode'> 123
<type 'unicode'> где
<type 'unicode'> 456

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