gistfile1.txt

class LazyRef(object):
  def __init__(self, fullname):
    self.fullname = fullname
    self.ref = None

  def __call__(self, *args, **kwargs):
    if not self.ref:
      modulename, objname = self.fullname.rpartition('.')
      module = __import__(modulename, globals(), locals())
      self.ref = module.__dict__[objname]
    return self.ref(*args, **kwargs)