I use `--` to represent an en dash for date ranges (some_report_2021-01-01--2021-12-31). I don't use times nearly as often, but I separate date from time using

I use `--` to represent an en dash for date ranges (some_report_2021-01-01--2021-12-31). I don't use times nearly as often, but I separate date from time using an underscore in those instances.