'Attempt to get cryptography\'s binding instance.
@raises NotImplementedError: If underlying pyOpenSSL is not based on
cryptography.
@return: cryptograpy bindings.
@rtype: C{cryptography.hazmat.bindings.openssl.Binding}'

def _getBinding(self):

    try:
        from OpenSSL._util import binding
        return binding
    except ImportError:
        raise NotImplementedError('This    version    of    pyOpenSSL    does    not    support    ECC.')
