It's fairly straight-forward to use. This isn't tested, but should work:

# load OpenSSL.crypto
from OpenSSL import crypto

# open it, using password. Supply/read your own from stdin.
p12 = crypto.load_pkcs12(open("/path/to/cert.p12", 'rb').read(), passwd)

# get various properties of said file.
# note these are PyOpenSSL objects, not strings although you
# can convert them to PEM-encoded strings.
p12.get_certificate()     # (signed) certificate object
p12.get_privatekey()      # private key.
p12.get_ca_certificates() # ca chain.

For more examples, have a look through the unit test code of pyopenssl. Pretty much every way you might want to use the library is there

See also here or without adverts here.

SSLContext was introduced in 2.7.9, you're using an old version of Python so it doesn't have this attribute.

Use cryptography.hazmat.primitives.serialization.pkcs12.load_key_and_certificates.

Example:

Copyfrom cryptography.hazmat.primitives.serialization import pkcs12

with open("cert.pfx", "rb") as f:
    private_key, certificate, additional_certificates = pkcs12.load_key_and_certificates(f.read(), b"1234")
print(certificate.not_valid_after)