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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 der_cert(der_data):
 """ Load a DER encoded certificate :param der_data: DER-encoded certificate :return: A cryptography.x509.certificate instance """

    if isinstance(der_data, str):
        der_data = bytes(der_data, 'utf-8')
    return x509.load_der_x509_certificate(der_data, default_backend())