#!/usr/bin/env python3

import subprocess

p = subprocess.Popen(["./test.sh"], stdin=subprocess.PIPE, stdout=subprocess.PIPE)
out, err = p.communicate(input='1')
print (out)

################################################################################

Traceback (most recent call last):
  File "/home/petya/eclipse/python3/sybprocess1.py", line 6, in <module>
    out, err = p.communicate(input='1')
  File "/usr/lib/python3.5/subprocess.py", line 801, in communicate
    stdout, stderr = self._communicate(input, endtime, timeout)
  File "/usr/lib/python3.5/subprocess.py", line 1431, in _communicate
    input_view = memoryview(self._input)
TypeError: memoryview: a bytes-like object is required, not 'str'