ImportError: No module named 'xmlrpclib'

I installed Electrum using

$ pip3 install --user https://github.com/spesmilo/electrum/archive/2.9.3.tar.gz
…
Successfully installed Electrum-2.9.3 PySocks-1.6.7 dnspython-1.15.0 ecdsa-0.13 jsonrpclib-0.1.7
pbkdf2-1.3 protobuf-3.4.0 pyaes-1.6.0 qrcode-5.3

Now when I start electrum, I get an ImportError: No module named ‘xmlrpclib’:

$ electrum 
Traceback (most recent call last):
  File "/home/hartmut/.local/bin/electrum", line 71, in check_imports
    import jsonrpclib
  File "/…/.local/lib/python3.5/site-packages/jsonrpclib/__init__.py", line 5, in <module>
    from jsonrpclib.jsonrpc import Server, MultiCall, Fault
  File "/…/.local/lib/python3.5/site-packages/jsonrpclib/jsonrpc.py", line 50, in <module>
    from xmlrpclib import Transport as XMLTransport
ImportError: No module named 'xmlrpclib'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/…/.local/bin/electrum", line 90, in <module>
    check_imports()
  File "/…/.local/bin/electrum", line 73, in check_imports
    sys.exit("Error: %s. Try 'sudo pip install <module-name>'"%e.message)
AttributeError: 'ImportError' object has no attribute 'message'

Python 3.5.3

Alternatively I tried with Python 2.7, but this failed to find ecdsa.