code: def is_entry_safe(self, entry):
          
          normalized = os.path.normpath(entry)
          if normalized.startswith(os.sep) or normalized.startswith(".." + os.sep):
              self.log([u"Entry '%s' is not safe", entry])
              return False
          self.log([u"Entry '%s' is safe", entry])
          return True
docs: Return ``True`` if ``entry`` can be safely extracted,
          that is, if it does start with ``/`` or ``../``
          after path normalization, ``False`` otherwise.
  
          :rtype: bool