I'm implementing a specification that, as the outermost data type, specifies a sequence

LogMessage ::= SEQUENCE {
   version INTEGER (4),
   ...
}

When encoded, I would expect the messages to always start with 30, but this is not the case. Indeed what I see when I look at the messages is that the inner part of the SEQUENCE is encoded, but the outer definition (30 and length field of payload) is omitted.

I cannot find why this is happening (the ASN.1 looks just "normal"). Is there a special mode in which this behavior can be seen? Of course I can "manually" trucate that leading data, but I would like to build a robust solution and if this is somehow defined in ASN.1, I'm sure my library (pyasn1) would have an option to set it.