sphinxcontrib.email: AttributeError (module 'string' has no attribute 'maketrans')

[architux]

An error occured after installing sphinxcontrib.email in virtualenv and including in extensions list in conf.py settings file. Seems to be the incompatibility with Python 3.x.
The whole traceback is the following:

# Sphinx version: 1.6.3
# Python version: 3.5.2 (CPython)
# Docutils version: 0.14 
# Jinja2 version: 2.9.6
# Last messages:

# Loaded extensions:
Traceback (most recent call last):
  File "/home/user/project/venv/lib/python3.5/site-packages/sphinx/cmdline.py", line 305, in main
    opts.warningiserror, opts.tags, opts.verbosity, opts.jobs)
  File "/home/user/project/venv/lib/python3.5/site-packages/sphinx/application.py", line 196, in __init__
    self.setup_extension(extension)
  File "/home/user/project/venv/lib/python3.5/site-packages/sphinx/application.py", line 456, in setup_extension
    self.registry.load_extension(self, extname)
  File "/home/user/project/venv/lib/python3.5/site-packages/sphinx/registry.py", line 196, in load_extension
    mod = __import__(extname, None, None, ['setup'])
  File "/home/user/project/venv/lib/python3.5/site-packages/sphinxcontrib/email.py", line 15, in <module>
    rot_13_trans = string.maketrans(
AttributeError: module 'string' has no attribute 'maketrans'