'Verify the validity of an RSA signature.
:attention: this function performs the plain, primitive RSA encryption
(*textbook*). In real applications, you always need to use proper
cryptographic padding, and you should not directly verify data with
this method. Failure to do so may lead to security vulnerabilities.
It is recommended to use modules
`Crypto.Signature.PKCS1_PSS` or `Crypto.Signature.PKCS1_v1_5` instead.
:Parameter M: The expected message.
:Type M: byte string or long
:Parameter signature: The RSA signature to verify. The first item of
the tuple is the actual signature (a long not larger than the modulus
**n**), whereas the second item is always ignored.
:Type signature: A 2-item tuple as return by `sign`
:Return: True if the signature is correct, False otherwise.'

def verify(self, M, signature):

    return pubkey.pubkey.verify(self, M, signature)
