+ """Given a MAC address, see if we know it's IP address and, if so,
+ return it. If not, return None.
+
+ Args:
+ mac: the MAC address to lookup. Should be formatted like
+ ab:cd:ef:g1:23:45.
+
+ Returns:
+ The IPv4 address associated with that MAC address (as a string)
+ or None if it's not known.
+ """
+ m = string_utils.extract_mac_address(mac)
+ if not m:
+ return None
+ m = m.lower()
+ if not string_utils.is_mac_address(m):
+ return None
+ return self.state.get(m, None)