code: def bits(self):
          
          if self._bits is None:
              value = self._DEFAULT_BITS.get(self.arch)
              if value is None:
                  raise NotImplementedError('Could not determine the default word size of %s architecture.' % self.arch)
              return value
          else:
              return self._bits
docs: The target architecture word size. One of :class:`Target.Bits`.