code: def create_sdist(self, tag):
          
          logger.info("Making tempdir for %s with tag %s...",
                      self.package, tag)
          self.wrapper.vcs.checkout_from_tag(tag)
          # checkout_from_tag() chdirs to a temp directory that we need to clean up
          # later.
          self.temp_tagdir = os.path.realpath(os.getcwd())
          logger.debug("Tag checkout placed in %s", self.temp_tagdir)
          python = sys.executable
          logger.debug(command("%s setup.py sdist" % python))
          tarball = find_tarball(self.temp_tagdir, self.package, tag)
          return tarball
docs: Create an sdist and return the full file path of the .tar.gz.