'Redefine if the name is already defined'

def redefine(self, name, loc, rename=True):

    if (name not in self.localvars):
        return self.define(name, loc)
    elif (not rename):
        return self.localvars.get(name)
    else:
        ct = self.redefined[name]
        self.redefined[name] = (ct + 1)
        newname = ('%s.%d' % (name, (ct + 1)))
        return self.define(newname, loc)
