sudo pip install cryptography --force-reinstall

$ sudo pip install cryptography --force-reinstall
The directory '/home/ubuntu/.cache/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
The directory '/home/ubuntu/.cache/pip' or its parent directory is not owned by the current user and caching wheels has been disabled. check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
Collecting cryptography
/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:318: SNIMissingWarning: An HTTPS request has been made, but the SNI (Subject Name Indication) extension to TLS is not available on this platform. This may cause the server to present an incorrect TLS certificate, which can cause validation failures. You can upgrade to a newer version of Python to solve this. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#snimissingwarning.
  SNIMissingWarning
/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:122: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. You can upgrade to a newer version of Python to solve this. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning.
  InsecurePlatformWarning
  Downloading cryptography-1.5.2.tar.gz (400kB)
    100% |████████████████████████████████| 409kB 3.0MB/s
Collecting idna>=2.0 (from cryptography)
  Downloading idna-2.1-py2.py3-none-any.whl (54kB)
    100% |████████████████████████████████| 61kB 12.3MB/s
Requirement already satisfied (use --upgrade to upgrade): pyasn1>=0.1.8 in /usr/local/lib/python2.7/dist-packages (from cryptography)
Requirement already satisfied (use --upgrade to upgrade): six>=1.4.1 in /usr/lib/python2.7/dist-packages (from cryptography)
Collecting setuptools>=11.3 (from cryptography)
  Downloading setuptools-28.0.0-py2.py3-none-any.whl (467kB)
    100% |████████████████████████████████| 471kB 2.8MB/s
Collecting enum34 (from cryptography)
  Downloading enum34-1.1.6-py2-none-any.whl
Collecting ipaddress (from cryptography)
  Downloading ipaddress-1.0.17-py2-none-any.whl
Collecting cffi>=1.4.1 (from cryptography)
  Downloading cffi-1.8.3-cp27-cp27mu-manylinux1_x86_64.whl (386kB)
    100% |████████████████████████████████| 389kB 3.4MB/s
Collecting pycparser (from cffi>=1.4.1->cryptography)
  Downloading pycparser-2.14.tar.gz (223kB)
    100% |████████████████████████████████| 225kB 5.8MB/s
Installing collected packages: idna, setuptools, enum34, ipaddress, pycparser, cffi, cryptography
  Found existing installation: setuptools 3.3
    Uninstalling setuptools-3.3:
      Successfully uninstalled setuptools-3.3
  Running setup.py install for pycparser ... done
  Running setup.py install for cryptography ... error
    Complete output from command /usr/bin/python -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-oUvjlY/cryptography/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record /tmp/pip-ckZ4zV-record/install-record.txt --single-version-externally-managed --compile:
    running install
    running build
    running build_py
    creating build
    creating build/lib.linux-x86_64-2.7
    creating build/lib.linux-x86_64-2.7/cryptography
    copying src/cryptography/__about__.py -> build/lib.linux-x86_64-2.7/cryptography
    copying src/cryptography/fernet.py -> build/lib.linux-x86_64-2.7/cryptography
    copying src/cryptography/exceptions.py -> build/lib.linux-x86_64-2.7/cryptography
    copying src/cryptography/utils.py -> build/lib.linux-x86_64-2.7/cryptography
    copying src/cryptography/__init__.py -> build/lib.linux-x86_64-2.7/cryptography
    creating build/lib.linux-x86_64-2.7/cryptography/x509
    copying src/cryptography/x509/extensions.py -> build/lib.linux-x86_64-2.7/cryptography/x509
    copying src/cryptography/x509/name.py -> build/lib.linux-x86_64-2.7/cryptography/x509
    copying src/cryptography/x509/base.py -> build/lib.linux-x86_64-2.7/cryptography/x509
    copying src/cryptography/x509/oid.py -> build/lib.linux-x86_64-2.7/cryptography/x509
    copying src/cryptography/x509/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/x509
    copying src/cryptography/x509/general_name.py -> build/lib.linux-x86_64-2.7/cryptography/x509
    creating build/lib.linux-x86_64-2.7/cryptography/hazmat
    copying src/cryptography/hazmat/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat
    creating build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives
    copying src/cryptography/hazmat/primitives/hashes.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives
    copying src/cryptography/hazmat/primitives/keywrap.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives
    copying src/cryptography/hazmat/primitives/cmac.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives
    copying src/cryptography/hazmat/primitives/serialization.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives
    copying src/cryptography/hazmat/primitives/hmac.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives
    copying src/cryptography/hazmat/primitives/constant_time.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives
    copying src/cryptography/hazmat/primitives/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives
    copying src/cryptography/hazmat/primitives/padding.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives
    creating build/lib.linux-x86_64-2.7/cryptography/hazmat/backends
    copying src/cryptography/hazmat/backends/multibackend.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends
    copying src/cryptography/hazmat/backends/interfaces.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends
    copying src/cryptography/hazmat/backends/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends
    creating build/lib.linux-x86_64-2.7/cryptography/hazmat/bindings
    copying src/cryptography/hazmat/bindings/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/bindings
    creating build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/twofactor
    copying src/cryptography/hazmat/primitives/twofactor/hotp.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/twofactor
    copying src/cryptography/hazmat/primitives/twofactor/totp.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/twofactor
    copying src/cryptography/hazmat/primitives/twofactor/utils.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/twofactor
    copying src/cryptography/hazmat/primitives/twofactor/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/twofactor
    creating build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/ciphers
    copying src/cryptography/hazmat/primitives/ciphers/algorithms.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/ciphers
    copying src/cryptography/hazmat/primitives/ciphers/base.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/ciphers
    copying src/cryptography/hazmat/primitives/ciphers/modes.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/ciphers
    copying src/cryptography/hazmat/primitives/ciphers/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/ciphers
    creating build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/asymmetric
    copying src/cryptography/hazmat/primitives/asymmetric/rsa.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/asymmetric
    copying src/cryptography/hazmat/primitives/asymmetric/dh.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/asymmetric
    copying src/cryptography/hazmat/primitives/asymmetric/ec.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/asymmetric
    copying src/cryptography/hazmat/primitives/asymmetric/dsa.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/asymmetric
    copying src/cryptography/hazmat/primitives/asymmetric/utils.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/asymmetric
    copying src/cryptography/hazmat/primitives/asymmetric/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/asymmetric
    copying src/cryptography/hazmat/primitives/asymmetric/padding.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/asymmetric
    creating build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/kdf
    copying src/cryptography/hazmat/primitives/kdf/concatkdf.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/kdf
    copying src/cryptography/hazmat/primitives/kdf/pbkdf2.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/kdf
    copying src/cryptography/hazmat/primitives/kdf/x963kdf.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/kdf
    copying src/cryptography/hazmat/primitives/kdf/kbkdf.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/kdf
    copying src/cryptography/hazmat/primitives/kdf/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/kdf
    copying src/cryptography/hazmat/primitives/kdf/hkdf.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/kdf
    creating build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/interfaces
    copying src/cryptography/hazmat/primitives/interfaces/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/primitives/interfaces
    creating build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    copying src/cryptography/hazmat/backends/openssl/rsa.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    copying src/cryptography/hazmat/backends/openssl/encode_asn1.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    copying src/cryptography/hazmat/backends/openssl/hashes.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    copying src/cryptography/hazmat/backends/openssl/cmac.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    copying src/cryptography/hazmat/backends/openssl/decode_asn1.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    copying src/cryptography/hazmat/backends/openssl/hmac.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    copying src/cryptography/hazmat/backends/openssl/backend.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    copying src/cryptography/hazmat/backends/openssl/ec.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    copying src/cryptography/hazmat/backends/openssl/dsa.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    copying src/cryptography/hazmat/backends/openssl/ciphers.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    copying src/cryptography/hazmat/backends/openssl/utils.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    copying src/cryptography/hazmat/backends/openssl/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    copying src/cryptography/hazmat/backends/openssl/x509.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/openssl
    creating build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/commoncrypto
    copying src/cryptography/hazmat/backends/commoncrypto/hashes.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/commoncrypto
    copying src/cryptography/hazmat/backends/commoncrypto/hmac.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/commoncrypto
    copying src/cryptography/hazmat/backends/commoncrypto/backend.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/commoncrypto
    copying src/cryptography/hazmat/backends/commoncrypto/ciphers.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/commoncrypto
    copying src/cryptography/hazmat/backends/commoncrypto/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/backends/commoncrypto
    creating build/lib.linux-x86_64-2.7/cryptography/hazmat/bindings/openssl
    copying src/cryptography/hazmat/bindings/openssl/binding.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/bindings/openssl
    copying src/cryptography/hazmat/bindings/openssl/_conditional.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/bindings/openssl
    copying src/cryptography/hazmat/bindings/openssl/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/bindings/openssl
    creating build/lib.linux-x86_64-2.7/cryptography/hazmat/bindings/commoncrypto
    copying src/cryptography/hazmat/bindings/commoncrypto/binding.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/bindings/commoncrypto
    copying src/cryptography/hazmat/bindings/commoncrypto/__init__.py -> build/lib.linux-x86_64-2.7/cryptography/hazmat/bindings/commoncrypto
    running egg_info
    writing requirements to src/cryptography.egg-info/requires.txt
    writing src/cryptography.egg-info/PKG-INFO
    writing top-level names to src/cryptography.egg-info/top_level.txt
    writing dependency_links to src/cryptography.egg-info/dependency_links.txt
    writing entry points to src/cryptography.egg-info/entry_points.txt
    warning: manifest_maker: standard file '-c' not found

    reading manifest file 'src/cryptography.egg-info/SOURCES.txt'
    reading manifest template 'MANIFEST.in'
    no previously-included directories found matching 'docs/_build'
    warning: no previously-included files matching '*' found under directory 'vectors'
    writing manifest file 'src/cryptography.egg-info/SOURCES.txt'
    running build_ext
    generating cffi module 'build/temp.linux-x86_64-2.7/_padding.c'
    creating build/temp.linux-x86_64-2.7
    generating cffi module 'build/temp.linux-x86_64-2.7/_constant_time.c'
    generating cffi module 'build/temp.linux-x86_64-2.7/_openssl.c'
    building '_openssl' extension
    creating build/temp.linux-x86_64-2.7/build
    creating build/temp.linux-x86_64-2.7/build/temp.linux-x86_64-2.7
    x86_64-linux-gnu-gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -I/usr/include/python2.7 -c build/temp.linux-x86_64-2.7/_openssl.c -o build/temp.linux-x86_64-2.7/build/temp.linux-x86_64-2.7/_openssl.o
    build/temp.linux-x86_64-2.7/_openssl.c:12:24: fatal error: pyconfig.h: No such file or directory
     #  include <pyconfig.h>
                            ^
    compilation terminated.
    error: command 'x86_64-linux-gnu-gcc' failed with exit status 1

    ----------------------------------------
Command "/usr/bin/python -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-oUvjlY/cryptography/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record /tmp/pip-ckZ4zV-record/install-record.txt --single-version-externally-managed --compile" failed with error code 1 in /tmp/pip-build-oUvjlY/cryptography/
/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:122: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. You can upgrade to a newer version of Python to solve this. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning.
  InsecurePlatformWarning