How to get time_coverage_start global attribute from TROPOMI?

I’m following a RUS Copernicus tutorial where he aggregates the TROPOMI NO2 products in the time dimension. However, he uses a ‘time_coverage_start’ and ‘time_coverage_end’ attribute to do this. When I try it, I get an error.

How do I get this attribute?

Code:

harpconvert -a "tropospheric_NO2_column_number_density_validity>75; derive(tropospheric_NO2_column_number_density [Pmolec/cm2]); bin_spatial(1600, 41, 0.01, 2000, -95, 0.01); derive(latitude {latitude}); derive(datetime_stop {time}); derive(datetime_start {time}); derive(longitude {longitude}); keep(tropospheric_NO2_column_number_density,latitude,longitude,latitude_bounds,longitude_bounds, time_coverage_start, time_coverage_end)" S5P_OFFL_L2__NO2____20210409T161510_20210409T175640_18079_01_010400_20210411T092742.nc output.nc

Error:
ERROR: cannot keep non-existent variable time_coverage_start