Return a X.509 certificate object by giving the name in the apk file

        :param filename: filename of the signature file in the APK
        :returns: a :class:`Certificate` certificate

def get_certificate(self, filename):
        """
        Return a X.509 certificate object by giving the name in the apk file

        :param filename: filename of the signature file in the APK
        :returns: a :class:`Certificate` certificate
        """
        cert = self.get_certificate_der(filename)
        certificate = x509.Certificate.load(cert)

        return certificate