You must install py4j Python module (pip install py4j) to use Zeppelin dynamic forms features

My zeppelin python interpreter use Anaconda 4.4.0
when i use the code from https://zeppelin.apache.org/docs/0.7.0/interpreter/python.html
(
%python

1. 1. 1. Input form
         print (z.input("f1","defaultValue"))

1. 1. 1. Select form
         print (z.select("f1",[("o1","1"),("o2","2")],"2"))

1. 1. 1. Checkbox form
         print("".join(z.checkbox("f3", [("o1","1"), ("o2","2")],["1"])))
         )
         the rusult is :
         You must install py4j Python module (pip install py4j) to use Zeppelin dynamic forms features

I had already installed py4j by pip install py4j,I use mach time to check but i cannot solve.The log have not error.I changed zeppelin.python to absolute path but cannot solve.
I cannot establish it cause by python,or by zeppelin.I need ask some body to help,thinks.
---------------------------------------------------------------------
python-interpreter-log:
INFO [2017-09-04 11:51:50,420] (

SchedulerFactory.java[jobFinished]:137) - Job remoteInterpretJob_1504497110420 finished by scheduler org.apache.zeppelin.python.PythonInterpreter893862673