'PyKeyboard' object has no attribute 'enter_key'

[yzw1993]

#!/usr/bin/python

-- coding: UTF-8 --

from pykeyboard.mac import PyKeyboard
from pymouse import PyMouse
import time

m = PyMouse()
k =PyKeyboard()
print(m.position())
time.sleep(1)
m.click(766,1375)
time.sleep(0.1)
m.click(1138,39)
time.sleep(0.1)
k.type_string("www.google.com")
k.tap_key(k.enter_key)

mac.py
Traceback (most recent call last):
File "/Users/yzw/PycharmProjects/pachong/mouse.py", line 16, in
k.tap_key(k.enter_key)
AttributeError: 'PyKeyboard' object has no attribute 'enter_key'