BadZipfile "file is not a zip file"

[MRAB]

webcomm wrote:
> On Jan 8, 8:02 pm, MRAB <goo... at mrabarnett.plus.com> wrote:
>> You're just creating a file called "data.zip". That doesn't make it
>> a zip file. A zip file has a specific format. If the file doesn't
>> have that format then the zipfile module will complain.
> 
> Hmm.  When I open it in Windows or with 7-Zip, it contains a text
> file that has the data I would expect it to have.  I guess that alone
> doesn't necessarily prove it's a zip file?
> 
> datum is something I'm downloading via a web service.  The providers 
> of the service say it's a zip file, and have provided a code sample
> in C# (which I know nothing about) that shows how to deal with it.
> In the code sample, the file is base64 decoded and then unzipped.
> I'm trying to write something in Python to decode and unzip the file.
> 
> I checked the file for comments and it has none.  At least, when I 
> view the properties in Windows, there are no comments.
> 
Ah, OK. You didn't explicitly say in your original posting that the
decoded data was definitely zipfile data. There was a thread a month ago
about gzip Unix commands which could also handle non-gzipped files and I
was wondering whether this problem was something like that. Have you
tried gzip instead?