code: public java.util.List<DBSecurityGroupMembership> getDBSecurityGroupMemberships() {
          if (dBSecurityGroupMemberships == null) {
              dBSecurityGroupMemberships = new com.amazonaws.internal.SdkInternalList<DBSecurityGroupMembership>();
          }
          return dBSecurityGroupMemberships;
      }
docs: <p>
  If the option requires access to a port, then this DB security group allows access to the port.
  </p>
  
  @return If the option requires access to a port, then this DB security group allows access to the port.