def numYields(self):
        """Extract numYields counter if available (lazy)."""
        if not self._counters_calculated:
            self._counters_calculated = True
            self._extract_counters()

        return self._numYields
def numYields ( self ) : if not self . _counters_calculated : self . _counters_calculated = True self . _extract_counters ( ) return self . _numYields
Extract numYields counter if available (lazy).