code: def findInNodeRegByHA(self, remoteHa):
          
          regName = [nm for nm, ha in self.registry.items()
                     if self.sameAddr(ha, remoteHa)]
          if len(regName) > 1:
              raise RuntimeError("more than one node registry entry with the "
                                 "same ha {}: {}".format(remoteHa, regName))
          if regName:
              return regName[0]
          return None
docs: Returns the name of the remote by HA if found in the node registry, else
          returns None