def open(self, path, flags):
    if DEBUG: print 'open called:', path, flags
    if path not in FILES.keys(): return -ENOENT
    return 0
def read(self, path, length, offset):
    if DEBUG: print 'READ called:', path, length, offset
    data = FILES[path]
    if len(data[offset:]) > length:
        return data[offset:offset+length]
    else: return data[offset:]