AttributeError: 'module' object has no attribute 'AM2320'

[Mantikor]

MicroPython v1.8.7-7-gb5a1a20a3 on 2017-01-09; ESP module with ESP8266
Type "help()" for more information.

from machine import I2C, Pin
import am2320
import os
os.listdir()
['boot.py', 'webrepl_cfg.py', 'am2320.py']
i2c = I2C(scl=Pin(5), sda=Pin(4), freq=20000)
dht = am2320.AM2320(i2c)
Traceback (most recent call last):
File "", line 1, in
AttributeError: 'module' object has no attribute 'AM2320'