Ошибка при запуске conda поднять ffiplatform.VerificationError (ошибка)

Question

Я работаю на компьютере с Ubuntu 16.04.У меня установлена ​​анаконда, и пару часов назад я отлично использовал ноутбук Jupyter для Джулии и Питона.Я установил / переустановил некоторые пакеты, но ничего необычного.

Однако после закрытия блокнотов и повторной попытки их открытия я получаю сообщение об ошибке:

jupyter notebook

Traceback (most recent call last):
  File "/home/user/anaconda2/bin/jupyter-notebook", line 4, in <module>
    import notebook.notebookapp
  File "/home/user/anaconda2/lib/python2.7/site-packages/notebook/notebookapp.py", line 60, in <module>
    from .services.contents.manager import ContentsManager
  File "/home/user/anaconda2/lib/python2.7/site-packages/notebook/services/contents/manager.py", line 16, in <module>
    from nbformat import sign, validate, ValidationError
  File "/home/user/anaconda2/lib/python2.7/site-packages/nbformat/__init__.py", line 33, in <module>
    from .validator import validate, ValidationError
  File "/home/user/anaconda2/lib/python2.7/site-packages/nbformat/validator.py", line 12, in <module>
    from jsonschema import ValidationError
  File "/home/user/anaconda2/lib/python2.7/site-packages/jsonschema/__init__.py", line 18, in <module>
    from jsonschema.validators import (
  File "/home/user/anaconda2/lib/python2.7/site-packages/jsonschema/validators.py", line 8, in <module>
    import requests
  File "/home/user/anaconda2/lib/python2.7/site-packages/requests/__init__.py", line 52, in <module>
    from .packages.urllib3.contrib import pyopenssl
  File "/home/user/anaconda2/lib/python2.7/site-packages/requests/packages/urllib3/contrib/pyopenssl.py", line 46, in <module>
    import OpenSSL.SSL
  File "/home/user/anaconda2/lib/python2.7/site-packages/OpenSSL/__init__.py", line 8, in <module>
    from OpenSSL import rand, crypto, SSL
  File "/home/user/anaconda2/lib/python2.7/site-packages/OpenSSL/rand.py", line 11, in <module>
    from OpenSSL._util import (
  File "/home/user/anaconda2/lib/python2.7/site-packages/OpenSSL/_util.py", line 7, in <module>
    binding = Binding()
  File "/home/user/anaconda2/lib/python2.7/site-packages/cryptography/hazmat/bindings/openssl/binding.py", line 89, in __init__
    self._ensure_ffi_initialized()
  File "/home/user/anaconda2/lib/python2.7/site-packages/cryptography/hazmat/bindings/openssl/binding.py", line 109, in _ensure_ffi_initialized
    libraries=libraries,
  File "/home/user/anaconda2/lib/python2.7/site-packages/cryptography/hazmat/bindings/utils.py", line 80, in build_ffi
    extra_link_args=extra_link_args,
  File "/home/user/anaconda2/lib/python2.7/site-packages/cffi/api.py", line 437, in verify
    lib = self.verifier.load_library()
  File "/home/user/anaconda2/lib/python2.7/site-packages/cffi/verifier.py", line 114, in load_library
    return self._load_library()
  File "/home/user/anaconda2/lib/python2.7/site-packages/cffi/verifier.py", line 225, in _load_library
    return self._vengine.load_library()
  File "/home/user/anaconda2/lib/python2.7/site-packages/cffi/vengine_cpy.py", line 158, in load_library
    raise ffiplatform.VerificationError(error)
cffi.ffiplatform.VerificationError: importing '/home/user/anaconda2/lib/python2.7/site-packages/cryptography/_Cryptography_cffi_4ed9e37dx4000d087.so': /home/user/anaconda2/lib/python2.7/site-packages/cryptography/_Cryptography_cffi_4ed9e37dx4000d087.so: undefined symbol: SSLv2_client_method

Я думаю, что это связано с анакондой, поскольку следующие команды вызовут ту же ошибку.

conda install jupyter 
pip install jupyter
pip install python-igraph

Я уже установил библиотеки, предложенные в ответах на этот вопрос ( meet cffi.ffiplatform.VerificationError при установке pyopenssl ).Но это не сработало.