pickle.load failing with ValueError: insecure string pickle

Tim Peters tim.one at comcast.net
Tue Feb 11 18:49:19 CET 2003

[carroll at tjc.com]
> I'm a relatively new Python user, using Pickle for the first time.
> pickle.load is dying with "ValueError: insecure string pickle"
> The object I'm trying to pickle is a fairly large (15,443 entries)
> dictionary of objects.  The objects are fairly straightforward -- all
> the attributes are relatively short strings.
> Here's my pickling/unpickling code (all together as a test case):
> ======================================
> picklefile = "handict.pickle"
> print "dumping..."
> pickleout = open(picklefile,"w")
> pickle.dump(hanchars,pickleout)
> pickleout.close

Bingo -- that didn't close the file, it merely retrieved the close method of
the file and then ignored it.  You want



> ...
> I want to use pickle because my dictionary is derived from a 25-meg
> input file.  It's more efficient to just process it once and pickle
> the dictionary for future use.

Yup, that's a good use for pickle.  Note that pickle's "binary mode" is more
efficient than its default "text mode".  A special caution for you, since
you said later you're running on Windows:  when you use the pickle binary
mode, you must also open your pickle files (for both reading and writing) in
binary mode ("rb" and "wb").

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