How do you translate this regular-expression idiom from Perl into Python?

Question

I switched from Perl to Python about a year ago and haven\'t looked back. There is only one idiom that I\'ve ever found I can do more easily in Perl than in Python:<

Answer 1

A minimalist DataHolder:

class Holder(object):
    def __call__(self, *x):
        if x:
            self.x = x[0]
        return self.x

data = Holder()

if data(re.search('foo (\d+)', string)):
    print data().group(1)

or as a singleton function:

def data(*x):
    if x:
        data.x = x[0]
    return data.x