docs: def find_trace_file(mname):
          """Tries to find the traces tdms file name
  
          Returns None if no trace file is found.
          """
          mname = pathlib.Path(mname)
          tname = None
  
          if mname.exists():
              cand = mname.with_name(mname.name[:-5] + "_traces.tdms")
              if cand.exists():
                  tname = cand
  
          return tname