code: def __parse_organizations(self, stream):
          
  
          for aliases in self.__parse_stream(stream):
              # Parse identity
              identity = self.__parse_alias(aliases[1])
              uuid = identity.email
  
              uid = self._identities.get(uuid, None)
  
              if not uid:
                  uid = UniqueIdentity(uuid=uuid)
                  identity.uuid = uuid
                  uid.identities.append(identity)
                  self._identities[uuid] = uid
  
              # Parse organization
              mailmap_id = aliases[0]
              name = self.__encode(mailmap_id[0])
  
              if name in MAILMAP_NO_ORGS:
                  continue
  
              org = Organization(name=name)
              self._organizations[name] = org
  
              enrollment = Enrollment(start=MIN_PERIOD_DATE, end=MAX_PERIOD_DATE,
                                      organization=org)
              uid.enrollments.append(enrollment)
docs: Parse organizations stream