(self)
return KeysView(self)
D.keys() -> a set-like object providing a view on D's keys
D.keys() -> a set-like object providing a view on D's keys
D . keys () - > a set - like object providing a view on D s keys
def keys(self):
        "D.keys() -> a set-like object providing a view on D's keys"
        return KeysView(self)
def keys ( self ) : return KeysView ( self )