Explicitely adds certificate to set of trusted in the store
        @param cert - X509 object to add

def add_cert(self, cert):
        """
        Explicitely adds certificate to set of trusted in the store
        @param cert - X509 object to add
        """
        if not isinstance(cert, X509):
            raise TypeError("cert should be X509")
        libcrypto.X509_STORE_add_cert(self.store, cert.cert)