How to install OpenSSL for Python

I need to install OpenSSL on my python2.7.

I tried

$ pip install pyopenssl

And I got the following

/usr/local/lib/python2.7/distutils/dist.py:267: UserWarning: Unknown distribution option: 'zip_safe'
  warnings.warn(msg)
running build
running build_py
running build_ext
building 'OpenSSL.crypto' extension
gcc -pthread -fno-strict-aliasing -g -O2 -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -I/usr/local/include/python2.7 -c OpenSSL/crypto/crypto.c -o build/temp.linux-x86_64-2.7/OpenSSL/crypto/crypto.o
In file included from OpenSSL/crypto/crypto.h:17,
                 from OpenSSL/crypto/crypto.c:15:
OpenSSL/crypto/x509.h:17:25: error: openssl/ssl.h: No such file or directory
In file included from OpenSSL/crypto/crypto.h:17,
                 from OpenSSL/crypto/crypto.c:15:
OpenSSL/crypto/x509.h:25: error: expected specifier-qualifier-list before ‘X509’
OpenSSL/crypto/x509.h:29: error: expected declaration specifiers or ‘...’ before ‘ASN1_TIME’
OpenSSL/crypto/x509.h:30: error: expected declaration specifiers or ‘...’ before ‘ASN1_TIME’
In file included from OpenSSL/crypto/crypto.h:18,
                 from OpenSSL/crypto/crypto.c:15:
OpenSSL/crypto/x509name.h:27: error: expected specifier-qualifier-list before ‘X509_NAME’
In file included from OpenSSL/crypto/crypto.h:19,
                 from OpenSSL/crypto/crypto.c:15:
OpenSSL/crypto/netscape_spki.h:24: error: expected specifier-qualifier-list before ‘NETSCAPE_SPKI’
In file included from OpenSSL/crypto/crypto.h:20,
                 from OpenSSL/crypto/crypto.c:15:
OpenSSL/crypto/x509store.h:25: error: expected specifier-qualifier-list before ‘X509_STORE’
In file included from OpenSSL/crypto/crypto.h:21,
                 from OpenSSL/crypto/crypto.c:15:
OpenSSL/crypto/x509req.h:25: error: expected specifier-qualifier-list before ‘X509_REQ’
In file included from OpenSSL/crypto/crypto.h:22,
                 from OpenSSL/crypto/crypto.c:15:
OpenSSL/crypto