                  if hasattr(manager, 'related'):  # Forward
                      self.queryset = manager.related.model._default_manager.all()
                  else:  # Reverse
                      self.queryset = manager.field.rel.to._default_manager.all()
              except:
                  raise
                  msg = ('Serializer related fields must include a `queryset`' +
                         ' argument or set `read_only=True')
                  raise Exception(msg)
  
 
</s> remove         except:
 </s> add         except Exception: </s> remove         except:
 </s> add         except Exception: </s> remove         except:
 </s> add         except KeyError: </s> remove except:
 </s> add except ImportError: </s> remove except:
 </s> add except ImportError:
            except Exception:
                  if hasattr(manager, 'related'):  # Forward
                      self.queryset = manager.related.model._default_manager.all()
                  else:  # Reverse
                      self.queryset = manager.field.rel.to._default_manager.all()
            except Exception:
                  raise
                  msg = ('Serializer related fields must include a `queryset`' +
                         ' argument or set `read_only=True')
                  raise Exception(msg)
  
keep keep keep keep replace keep keep keep keep keep
 Purge naked excepts.

Most of these had obvious exceptions which would be thrown. Some I'm not
sure about but they should at least catch only Exception so as not to
ignore SystemExit and other inappropriate Error classes. 
rest_framework/relations.py