'Verifies a certificate request using the supplied public key
:param key: a public key
:return: True if the signature is correct.
:raise OpenSSL.crypto.Error: If the signature is invalid or there is a
problem verifying the signature.'

def verify(self, pkey):

    if (not isinstance(pkey, PKey)):
        raise TypeError('pkey    must    be    a    PKey    instance')
    result = _lib.X509_REQ_verify(self._req, pkey._pkey)
    if (result <= 0):
        _raise_current_error()
    return result
