ZipStream class does not exist, we should use ZipFile class instead.

By trying auto completion in an ipython shell for "zipstream." that's what i get :
zipstream.BZIP2_VERSION zipstream.str
zipstream.LZMA_VERSION zipstream.stringCentralDir
zipstream.PointerIO zipstream.stringDataDescriptor
zipstream.ZIP64_LIMIT zipstream.stringEndArchive
zipstream.ZIP64_VERSION zipstream.stringEndArchive64
zipstream.ZIP_BZIP2 zipstream.stringEndArchive64Locator
zipstream.ZIP_DEFLATED zipstream.stringFileHeader
zipstream.ZIP_FILECOUNT_LIMIT zipstream.struct
zipstream.ZIP_LZMA zipstream.structCentralDir
zipstream.ZIP_MAX_COMMENT zipstream.structEndArchive
zipstream.ZIP_STORED zipstream.structEndArchive64
zipstream.ZipFile zipstream.structEndArchive64Locator
zipstream.ZipInfo zipstream.structFileHeader
zipstream.bytes zipstream.sys
zipstream.compat zipstream.time
zipstream.crc32 zipstream.unicode_literals
zipstream.os zipstream.with_statement
zipstream.print_function zipstream.zipfile
zipstream.stat zipstream.zlib

So, in every example, it should be : "z = ZipFile(mode='w', compression=ZIP_DEFLATED)"
And not "ZipStream"