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A csv (comma delimited) file, where lines have an extra trailing delimiter, seems to confuse pandas.read_csv. (The data file is [1])
It treats the extra delimiter as if there's an extra column. So there's one more column than what headers require. Then pandas.read_csv takes the first column as row labels. The overall effect is that columns and headers are not aligned any more - the first column becomes row labels, the second column is named by first header, etc.
It is quite annoying. Any idea how to tell pandas.read_csv do the right thing? I couldn't find one.
Great book, BTW.
[1]: 2012 FEC Election Database from chapter 9 of the book Python for Data Analysis