desc is a list of lists (or nested list) that defines the structure of the data fields for the DesCSATTB class. Each inner list represents a field in the data structure, with the following components:
- Field Name: A string representing the name of the field (e.g., "qual_flag_att").
- Description: A string describing the purpose of the field (e.g., "Attitude Data Quality Flag").
- Field Length: An integer or a reference indicating the size of the field (e.g., 1 or "f.reserved_len").
- Data Type: The type of data stored in the field (e.g., int, float, or None).
- Optional Metadata: A dictionary (optional) that provides additional information about the field, such as formatting or conditions.