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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 serialize_cert_to_der(cert_obj):
 """Serialize certificate to DER. Args: cert_obj: cryptography.Certificate Returns: bytes: DER encoded certificate """

    return cert_obj.public_bytes(
        cryptography.hazmat.primitives.serialization.Encoding.DER
    )