OpenSSL binding error on Ubuntu 16.04.3

[sgk]

After installing by pip, the yotta login command results in AttributeError.

$ yotta
usage: yotta [-h] [--version] [-v] [--plain] [--colourful] [--noninteractive]
             [-t TARGET] [--config path/to/config.json]
             <subcommand> ...
yotta: error: too few arguments
$ yotta login
From cffi callback <function _verify_callback at 0x7fa122d38758>:
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/OpenSSL/SSL.py", line 313, in wrapper
    _lib.X509_up_ref(x509)
AttributeError: 'module' object has no attribute 'X509_up_ref'

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^Cwarning: interrupted
$ 

[sgk]

I found this can be corrected by installing latest pyopenssl separately.

$ pip install pyopenssl yotta

[sgk]

You may want to add note to the installation page http://docs.yottabuild.org/#installing-on-linux

[thegecko]

Similar issues have also been fixed using:

$ pip install --upgrade setuptools
$ pip install --upgrade pyOpenSSL