Returning a linked table column as a dictionary

Anvil Q&A
11 

  for d in my_list:
    my_inner_dicts=[dict(row) for row in d['cust_transaction']]
    for e in my_inner_dicts:
      details = [dict(row) for row in e['details']]
      e.update({'details': details})
      
    d.update({'cust_transaction': my_inner_dicts})

getting this error:
ValueError: dictionary update sequence element #0 has length 1; 2 is required