What is the relationship between tx_osnr and power_dbm parameters in eqpt_config.json?

[alittleice]

In the info.py file code, there is a confusion point is not clear, I would like to ask everyone to help solve it.
Here's the part of the code that was confusing：
signal = full(number_of_channels, signal) baud_rate = full(number_of_channels, baud_rate) roll_off = full(number_of_channels, roll_off) slot_width = full(number_of_channels, slot_width) if slot_width is not None else \ ceil((1 + roll_off) * baud_rate / DEFAULT_SLOT_WIDTH_STEP) * DEFAULT_SLOT_WIDTH_STEP chromatic_dispersion = full(number_of_channels, chromatic_dispersion) pmd = full(number_of_channels, pmd) pdl = full(number_of_channels, pdl) latency = full(number_of_channels, latency) nli = zeros(number_of_channels) ase = zeros(number_of_channels) delta_pdb_per_channel = full(number_of_channels, delta_pdb_per_channel) tx_osnr = full(number_of_channels, tx_osnr) label = full(number_of_channels, label)