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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def _certificate_required(cls, hostname, port=XCLI_DEFAULT_PORT,
                              ca_certs=None, validate=None):
        '''
        returns true if connection should verify certificate
        '''
        if not ca_certs:
            return False

        xlog.debug("CONNECT SSL %s:%s, cert_file=%s",
                   hostname, port, ca_certs)
        certificate = ssl.get_server_certificate((hostname, port),
                                                 ca_certs=None)
        # handle XIV pre-defined certifications
        # if a validation function was given - we let the user check
        # the certificate himself, with the user's own validate function.
        # if the validate returned True - the user checked the cert
        # and we don't need check it, so we return false.
        if validate:
            return not validate(certificate)
        return True