When creating secs_nanos column the secs column has to be an integer...
When creating the dataset["secs_nanos"] column the dataset["secs"] column has to be integers otherwise the decimals are added twice. The column dataset["secs"] contains the time in seconds with decimals. When adding the nanos (dataset["nanos"]) to dataset["secs"] to create dataset["secs_nanos"], the dataset["secs"] must be converted to integers otherwise the decimals are added twice, as mentioned earlier.