def METHOD_NAME(tx):
    """
    Make the signature in vin 0 of a tx non-DER-compliant,
    by adding padding after the S-value.
    """
    scriptSig = CScript(tx.vin[0].scriptSig)
    newscript = []
    for i in scriptSig:
        if (len(newscript) == 0):
            newscript.append(i[0:-1] + b'\0' + i[-1:])
        else:
            newscript.append(i)
    tx.vin[0].scriptSig = CScript(newscript)