使用
itertools.groupby:
>>> foo = "SSYYNNOOPPSSIISS">>> import itertools>>> ''.join(ch for ch, _ in itertools.groupby(foo))'SYNOPSIS'

使用
itertools.groupby:
>>> foo = "SSYYNNOOPPSSIISS">>> import itertools>>> ''.join(ch for ch, _ in itertools.groupby(foo))'SYNOPSIS'