code: public Collection<Retrospective> getRetrospectives(
              RetrospectiveFilter filter) {
          filter = (filter == null) ? new RetrospectiveFilter() : filter;
  
          filter.team.clear();
          filter.team.add(this);
          return getInstance().get().retrospectives(filter);
      }
docs: Gets the Retrospectives assigned to this Team.
  
  @param filter Criteria to filter Retrospectives on.
  @return assigned Retrospectives.