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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 decode_cert(cert):
 """Convert an X509 certificate into a Python dictionary This function converts the given X509 certificate into a Python dictionary in the manner established by the Python standard library's ssl module. """


    ret_dict = {}
    subject_xname = X509_get_subject_name(cert.value)
    ret_dict["subject"] = _create_tuple_for_X509_NAME(subject_xname)

    notAfter = X509_get_notAfter(cert.value)
    ret_dict["notAfter"] = ASN1_TIME_print(notAfter)

    peer_alt_names = _get_peer_alt_names(cert)
    if peer_alt_names is not None:
        ret_dict["subjectAltName"] = peer_alt_names

    return ret_dict