Python: How do I delete periods occurring alone in a CSV file?
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I have a bunch of CSV files.  In some of them, missing data are represented by empty cells, but in others there is a period.  I want to loop over all my files, open them, delete any periods that occur alone, and then save and close the file.

I've read a bunch of other questions about doing whole-word-only searches using re.sub().  That is what I want to do (delete . when it occurs alone but not the . in 3.5), but I can't get the syntax right for a whole-word-only search where the whole word is a special character ('.').  Also, I'm worried those answers might be a little different in the case where a whole word can be distinguished by tab and newlines too.  That is, does /b work in my CSV file case?