Missing trailing fields in CSV file
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Pandas Version:  0.10.0.dev-e80d24e

I get the following error when reading a CSV file that was previously correctly read with the old Pandas 0.09 read_csv() code.

CParserError: Error tokenizing data. C error: Expected 41 fields in line 7123, saw 40

Looks like the tokenizer will fail if it encounters a line with missing data at the end if there are no trialling commas for the last missing column(s):

A,B,C,D
1,2,3,4 <-OK
1,3,3,  <-OK
1,4,5   <-Fail :(

I know this is not a clean CSV but having this feature may save some headaches when reading in files, especially since some CSV writers do not add the trailing commas.

Thanks,
-Gagi
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