<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def is_extended_validation(self, certificate: Certificate) -> bool: """Is the supplied server certificate EV? """

        if not self.ev_oids:
            raise ValueError('No EV OIDs supplied for {} store - cannot detect EV certificates'.format(self.name))

        try:
            cert_policies_ext = certificate.extensions.get_extension_for_oid(ExtensionOID.CERTIFICATE_POLICIES)
        except ExtensionNotFound:
            return False

        for policy in cert_policies_ext.value:
            if policy.policy_identifier in self.ev_oids:
                return True
        return False