'ensure that an args-joined path exists (by default as
a file). if you specify a keyword argument \'dir=True\'
then the path is forced to be a directory path.'

def ensure(self, *args, **kwargs):

    p = self.join(*args)
    if kwargs.get('dir', 0):
        return p._ensuredirs()
    else:
        p.dirpath()._ensuredirs()
        if (not p.check(file=1)):
            p.open('w').close()
        return p
