[Zope] Accessing file object to upload in an external method

[Simon ALEXANDRE]

Hi,

I'm new in zope and I'm trying to upload a file on zope using localfs. 
I already done it through a little basic html page + python script.

I would like now use it in an external method.

Here is the line added in the external method: 

self.dir_filesystem.manage_upload(file=self.zipfile)

zipfile is the name of the file in the html form (File <INPUT TYPE="file"
NAME="zipfile" SIZE="25" VALUE="">)

I got the following error: 

File "D:\\D-Side/qross/zope_gui\Extensions\Project.py", line 31, in
PrepareToCreateOrUpdateObject
    self.dir_filesystem.manage_upload(file=self.zipfile)
 exceptions.AttributeError: zipfile

I'm quite sure that my error lies in the way I reference 'zipfile' but I
don't know how to proceed

Thanks for your help

Simon