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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 _op_msg_compressed(flags, command, identifier, docs, check_keys, opts, ctx):
 """Internal OP_MSG message helper."""

    msg, total_size, max_bson_size = _op_msg_no_header(
        flags, command, identifier, docs, check_keys, opts)
    rid, msg = _compress(2013, msg, ctx)
    return rid, msg, total_size, max_bson_size