gistfile1.py

#!/usr/bin/python
#

class Burton (object):

    def __init__ (self):
        self.foo = 1

    def __enter__ (self):
        return self

    def __exit__ (self, t, v, tr):
        return self

    def render (vals):
        fmt = 'a %i, or %d'
        return fmt % vals

def render (vals):
    fmt = 'a %i, or %d'
    return fmt % vals

if __name__ == '__main__':

    v = [1, 2]
    r = render(tuple(v))
    print r

    with Burton() as b:
        r2 = b.render(tuple(v))
        print r2