<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _parse_nexus_vni_range(self, tunnel_range):
 """Raise an exception for invalid tunnel range or malformed range."""

        for ident in tunnel_range:
            if not self._is_valid_nexus_vni(ident):
                raise exc.NetworkTunnelRangeError(
                    tunnel_range=tunnel_range,
                    error=_("%(id)s is not a valid Nexus VNI value.") %
                    {'id': ident})

        if tunnel_range[1] < tunnel_range[0]:
            raise exc.NetworkTunnelRangeError(
                tunnel_range=tunnel_range,
                error=_("End of tunnel range is less than start of "
                        "tunnel range."))