code: def upload_release(self):
          
          self.before_upload_release()
  
          with settings(user=self.user):
              with app_bundle():
                  local_bundle = env.local_bundle
                  env.bundle = '/tmp/' + os.path.basename(local_bundle)
                  file_upload(env.bundle, local_bundle)
  
              # Extract the bundle into a release folder
              current_release_link = self.releases_dir + '/current'
              previous_release_link = self.releases_dir + '/previous'
              release_dir = self.releases_dir + '/' + env.release
  
              dir_ensure(release_dir)
              with cd(release_dir):
                  run('tar -xvf ' + env.bundle)
  
              # Delete the remote bundle
              run('rm ' + env.bundle)
  
              # Remove previous release link
              if file_exists(previous_release_link):
                  run('rm ' + previous_release_link)
  
              # Move current to previous
              if file_exists(current_release_link):
                  run('mv %s %s' % (current_release_link, previous_release_link))
  
              # Link the current release
              file_link(release_dir, self.releases_dir + "/current")
  
              # Install app dependencies
              with cd(current_release_link):
                  with prefix('workon ' + self.name):
                      run('pip install -r requirements.txt')
  
          self.after_upload_release()
docs: Upload an application bundle to the server for a given context