code: def gatherBy(self, func):
          'Generate only rows for which the given func returns True.'
          for i in rotate_range(len(self.rows), self.cursorRowIndex):
              try:
                  r = self.rows[i]
                  if func(r):
                      yield r
              except Exception:
                  pasf gatherBy(self, func):
          'Generate only rows for which the given func returns True.'
          for i in rotate_range(len(self.rows), self.cursorRowIndex):
              try:
                  r = self.rows[i]
                  if func(r):
                      yield r
              except Exception:
                  pass
docs: Generate only rows for which the given func returns True.