Not that does anything except to confirm the pointless of that selection criterion:

  % python -mtimeit -s 'x=1' 'x<<3'
  10000000 loops, best of 3: 0.061 usec per loop
  % python -mtimeit -s 'x=1' 'x*8'
  10000000 loops, best of 3: 0.0602 usec per loop

  % pypy -mtimeit -s 'x=1' 'x<<3'
  1000000000 loops, best of 3: 0.00103 usec per loop
  % pypy -mtimeit -s 'x=1' 'x*8'
  1000000000 loops, best of 3: 0.00103 usec per loop